This is the area in which the GLS’s sheer size most counts against it, as ultimately you can’t deny the laws of physics. On pretty much any road other than a dual carriageway or wide motorway – and especially in congested city streets – you’re conscious and probably wary of the car’s size. Threading it down country lanes is made all the harder by the unfortunate combination of a vast amount of play around the straight-ahead, and the lack of feedback in the steering. Worse still, in the base AMG Line car, the body rolls so much in corners that it accentuates any steering input, making it hard to keep the car exactly where you want it. This is a big, ponderous car, and in a succession of bends – even a relatively swiftly taken roundabout – it’s a combination that can leave passengers rather green around the gills. So, it’s welcome news that higher-spec models come with the Active Curve System (a costly option on the AMG Line model), which reduces the body roll and makes the car more agile. Even with it, though, the GLS is not as rewarding to drive as other seven-seat SUVs such as, say, a Land Rover Discovery or Volvo XC90. At least the standard air suspension gives a comfortable and refined ride – particularly on the motorway – as long as you keep the car in ‘Comfort’ mode. In ‘Sport’ mode on the AMG Line car, we found that the ride became too firm, especially at low speeds. We found the GLS was at its best when using the 'Individual' drive mode - giving you the throttle and steering response of 'Sport' mode, but keeping the plush and pillowy ride quality from the 'Comfort' setting.