New Lexus RX 450h SUV

Going up against cars as talented as the BMW X5, Audi Q7, and Porsche Cayenne meant Lexus needed a way for its big SUV to stand out. Fortunately, the RX is probably one of the most dramatic looking 4x4s money can buy. The enormous 'spindle' grille at the front is wide enough to swallow a supermini, and the bodywork itself is all sharp lines and angles, with swept back LED headlights, a 'floating' roofline, and boxy wheel arches. It's nothing if not distinctive, and the standard models come with 18-inch alloys. Move up the range to a Luxury, and you get 20-inch wheels and LED cornering fog lights, too. The boldest version is the F Sport, with sporty design cues including its own unique mesh grille design, lowered bumpers and satin chrome detailing running along the sills. It may not be quite as imposing as, say, a Range Rover Sport, but we can see many buyers picking an RX on the strength of its looks alone.

One of the RX's biggest assets is its sumptuous cabin. While the outside of the car is all cutting-edge design and wild styling, the interior feels far more like one of the brand's traditional luxury saloons. That means big, comfortable seats that are really supportive, shiny wood veneers, soft leather and a large analogue clock in the centre of the dashboard. Its not the most cohesive interior in this class; some rivals, such as the Volvo XC90 for example, are less fussy, with fewer buttons and clashing materials. However, few (if any) SUVs are this well built. Every switch and surface your fingers come into contact with exudes an air of real quality. The ergonomics are slightly less impressive, however. On top of the dash sits a huge 12.3-inch screen (or 8.0-inches on lower spec models) but the infotainment system is controlled by a mouse-like pointer, which is overly sensitive, making it fiddly to operate, while some of the many menus defy conventional logic and and needlessly complicated. Still, at least the standard electrically adjustable seats mean it won't take long to find a suitably comfortable driving position. Visibility is generally good too, although the sloping roof does create a sizeable blind spot when reversing.

Although the RX still shares much of its mechanical components with the previous model, it has undergone a significant growth spurt, and is 12cm longer than before. Most of that added space is between the front and rear wheels, which means more passenger space inside, particularly for those in the back row. These rear seats slide, too, so a tall adult can sit quite comfortably behind a tall driver, and still have plenty of knee- and legroom to spare. The steeply raked roofline does come at the expense of headroom, especially on high-spec models that are also fitted with a full-length glass sunroof, but even tall occupants won't feel unduly cramped. However, while everyone inside will be travelling in comfort, they might need to leave their bags behind, due to the relatively small boot. The RX has a nice flat loading bay, which can be accessed automatically by waving your hand across a sensor fitted in the Lexus badge. Unfortunately, the load bay is quite shallow, and the sloped glass tailgate robs even more room. With only 453 litres of space with the rear seats up, the RX falls well short of the Audi Q7, BMW X5 and Volvo XC90 in this area, and again, unlike two of those rivals mentioned, you can't fit the Lexus with seven seats either.

In spite of the sporty styling, the RX is no athlete when it comes to its handling balance. The combination of the skinny tyres, heavy battery back and softly-sprung suspension mean the front wheels will start to wash wide in tighter turns long before rivals like the Porsche Cayenne and BMW X5. Keep your inputs smooth and deliberate, though, and the RX remains steady and composed through sweeping bends, and the trade-off in agility reaps its rewards on the motorway, where the RX rides really nicely, soaking up all but the biggest bumps and jolts. Some models come with adaptive suspension, which allows the driver to choose between a soft, cosseting ride, or a firmer setup designed for tidier handling. You'd have to be concentrating pretty hard to notice any real change, though, no matter which of the five different driving modes you decide to use. If you value comfort and refinement, the RX is one of the best big SUVs around, but a lot of other 4x4s are more fun, and more capable off-road.

Buyers have two different engines to choose from. The first is an entry-level 2.0-litre turbo petrol, which produces 235bhp, comes with either front- or four-wheel drive, and is paired with a six-speed automatic gearbox. It's good for 0-62mph in 9.2 seconds, (in front-wheel drive spec) but can sometimes struggle to haul around the RX's hefty body. So, most buyers are likely to opt for the RX 450h instead - the 'h' stands, of course, for 'hybrid'. This version is only available with four-wheel drive, but with a much bigger 3.5-litre V6 petrol engine helped out by an on-board electric motor, it feels a lot quicker getting up to speed. Driven gently, it's a really smooth, refined powertrain, but try and hustle it along too quickly and the CVT gearbox gets flustered, holding the engine at high revs needlessly. Still, with a combined output of 308bhp, it never feels slow. That said, if you're stepping into the RX from a punchy modern diesel, you might miss some mid-range clout on the motorway.

Prices for the four-wheel drive versions of the RX sit very close to its competitors; the BMW X5 starts slightly below the Lexus, but it undercuts its rivals from Audi, Mercedes and Land Rover. That's before you've factored in the savings you'll make from the low CO2 output (on 18-inch wheels the RX 450h emits just 120g/km), which is considerably lower than anything with a diesel engine, and means lower costs on both VED and company car tax. The skinny tyres will be cheaper to replace than on sportier SUVs, while Lexus models (due to their rarity) enjoy traditionally strong residual values, along with lower-than-average insurance ratings. Only full plug-in hybrids will be cheaper to run for fleet buyers, and those all cost much more to buy. Beware, though, that on longer motorway runs, when there is little benefit to the hybrid system, fuel economy is unlikely to creep beyond the 35mpg mark, and the small tank means you'll have to stop a lot.

Lexus is one of the most trusted brands in the business when it comes to reliability, finishing top of several recognised industry surveys. The previous generation RX is a traditionally strong performer, too, with above-average reliability, low repair costs, and no trouble with the major mechanical parts including the engine, gearbox and steering. This model shares most of its parts with that car, so it should continue this strong reputation for reliability going forward. The only issue worth mentioning is that several owners did report problems with the cooling system. However, drivers posting their own reviews on the www.autotrader.co.uk website reported no such issues, and were universal in their praise of the RX's durability, and dealer service. Although sister brand Toyota offers a five-year warranty, Lexus only provides a three-year policy, with a mileage limit of 60,000 miles, but that's broadly similar to most of its rivals in the premium SUV class.

Just like one of its main rivals - the Volvo XC90 - the RX takes safety very seriously indeed. It comes with ten airbags, more than any other big SUV, and every model has an exhaustive list of standard safety equipment that includes items that are usually only offered as pricey options. All the models in the range have adaptive cruise control, lane departure warning, lane keep assist, traffic sign recognition (so you always know the speed limit) and hill start assist, too. All this helped the RX achieve a maximum five-star score from Euro NCAP, with very high marks for driver and passenger protection. The usual systems also feature, with traction and stability control, tyre pressure monitors, plus autonomous braking at low and medium speeds. You'll honestly struggle to find another SUV that comes close to offering this much safety technology as standard.

Lexus is almost as generous with its standard equipment roster as it is with safety kit. Every RX comes with dual-zone climate control, eight-way powered, heated and ventilated front seats, front and rear parking sensors, keyless entry and start, sat-nav, DAB radio, Bluetooth and two USB ports for charging your electronic devices. All but the front-drive 'S' model get leather upholstery, and from the 'Luxury' trim upwards, all cars come equipped with heated and reclining rear seats, too. The higher grades also come with an upgraded 12.0-inch sat-nav screen, a high-end infotainment system with DVD capabilities, a wireless charging tray for compatible smartphones, reversing camera and powered tailgate. One option that is well worth considering if you do have deep enough pockets is the peerless Mark Levinson stereo, which sounds fantastic. The vast majority of other SUVs come without many of these luxuries, or require you to add them as pricey options, which quickly inflates the price you end up paying, whereas the RX comes with virtually everything you need included, unless you do fancy indulging in the incredible Hi-Fi we mentioned above.

If you want an SUV that is affordable to run, relaxing to drive and beautifully built inside, then the RX ticks all of those boxes. Its superb refinement, strong equipment levels and low CO2 all make it an interesting alternative to a diesel 4x4. However, if you want to do any serious off-roading, need space to seat seven, or a massive boot, then get a Volvo XC90 instead.