Category: Large 4x4s 
Price Range: £67,485 to £67,485
Road presence, performance, Mercedes image
Absolutely huge exterior, but cabin not that roomy; M-Class is better-looking
Only consider the GL if you absolutely have to have seven seats and off-roading capability - or want to make a big statement. The R-Class and M-Class are more practical options and cost thousands less.
For a beast that weighs nearly two-and-a-half tonnes, the GL acquits itself remarkably well. The speed-sensitive steering responds swiftly to inputs, with good precision making it easy to fix a cornering line that doesn't need constant adjustment.
Airmatic suspension is standard on UK GLs, as is the Adaptive Damper System (ADS). In Sport mode the ADS helps tie down the GL's body control through dips and surprise off-camber moments, but the ride predictably suffers. In Comfort mode, the ride is really very good, but you do trade off a bit of body control, which is again a predictable outcome.
The 4Matic permanent four-wheel drive system splits torque 50:50 front to rear - in tight corners you can feel the front wheels helping to pull the GL through, which is a rather reassuring feeling.
For off-road going, Mercedes aimed to invest the GL with credentials good enough to stand comparison with a Range Rover. So along with permanent four-wheel drive, there is a low-range, two-speed transfer case with multiple-disc limited slip differential, which can be locked for really serious going.
To match Land Rover's Hill Descent Control, the GL features Downhill Speed Regulation, which trumps Land Rover's system by offering a feature that allows the driver to set the maximum descent speed.
Then there is the amusingly titled Off-Road Pro system (standard fit in UK), which allows the Airmatic system to increase ride height by 307mm. This gives the GL an impressive wading depth of 600mm.
The full five stars for the GL 500 and GL 450 petrol models, although the diesels are expected to take around 80% of sales in Europe.
The GL 420 CDI's a top performer, too: this 306bhp engine is good for 0-60mph in 7.2 seconds and it has immense resources of torque - 516lb-ft peaking at 2,200-2,600rpm. It's quicker, with more mid-range strength, than the 340bhp 4.6 litre V8 petrol unit (GL 450), which develops a very respectable 339lb-ft of torque from as low as 2,700rpm; this results in a 0-62mph sprint in 7.6secs and a top speed of 146mph. Again, this is a very respectable result for a large SUV, and the GL feels every bit as lively as those numbers suggest.
The 388bhp/391lb-ft GL 500 is the daddy, however (Mercedes says there's no plan for a GL 65 AMG, but we wouldn't rule it out). Official figures claim a 0-60 time of 6.6 seconds and a near-150mph top speed, and it lives up to the on-paper boasts. It sounds the part, too, with a sportier exhaust note than the GL 420 which is, admittedly, the sensible pick of the bunch and no less rewarding to drive in its own way.
The GL 320 CDI (224bhp/376lb ft) is a little less inspiring: it's hardly slow or sluggish (130mph, 0-60 in 9.5 seconds) but it lacks the verve of the others. If you're spending this much on a vehicle, you may as well go for the full effect.
The seven-speed 7G-Tronic gearbox is a good match for the GL, too, with any of the four engine variants and is less prone to hunting around for the right gear as in smaller-engined ML-Class models. This auto 'box also has a manual sequential shift feature, which uses rocker switches on the back of the steering wheel. When you're pressing on a bit, this can be quite handy, allowing you to instantly drop down a gear or two for powering through tight corners.
