Unlike early plug-in hybrid systems developed by Mercedes, here the brakes impart confidence; there's proper feel and linear qualities to the pedal. The amount of electric energy regenerated under braking, meanwhile, is very impressive. It’s never going to save you from having to top up the battery from time to time, but there has been a marked advance in this area, because it's now achieved via all four wheels rather than just two.
When it comes to recharging the battery, the GLE 350de holds one decisive advantage over many of its upmarket plug-in hybrid SUV rivals in that it supports charging at a rate of up to 60kW, at which Mercedes claims a full recharge takes just 30mins. With a claimed 62 mile electric range and markedly improved regeneration qualities, most commutes can be achieved on battery energy stores alone.
The added weight brought on by its complex driveline has robbed the suspension of some of its compliance. However, with Mercedes' latest air spring technology, the GLE 350de still manages to deliver a quiet and cosseting ride that suites its interior ambience.
The dashboard and controls, including its generously dimensioned digital instrument and infotainment displays, are high in quality and lend the new GLE a markedly more upmarket air than its predecessor. The driving position and seats, meanwhile, are terrific.
Should I buy one?
The GLE 350de is well worth considering if you’re in the market for a luxury SUV, especially if you spend a good part of your time on urban roads and are therefore seeking zero-emissions compatibility but also head out on occasional longer trips.
With a torque-laden electric motor and the largest-capacity battery in its class, the GLE 350de delivers what many plug-in hybrids can’t – namely a truly extended electric-only range. And for longer journeys, you’ve got the inherent frugality of a diesel engine, albeit one that sometimes has to work hard to shift the new Mercedes-Benz model’s hefty weight, as back up.
Its best work, however, is done in hybrid mode, where the qualities of the electric motor and combustion engine combine to provide more than adequate performance.
Whether this is the right GLE variant for you will depend on your purchase options. However, its appeal as a company car is clear, thanks to its 29g/km official CO2 emissions rating.
The official combined cycle consumption claim of 256.8mpg – the result of a convoluted EU-mandated test procedure that's heavily weighted towards electric running – is clearly absurd. But if you’re prepared to charge the GLE 350de regularly, you might just manage to get by without using a drop of diesel in everyday driving. Otherwise, you have a big SUV carrying a heavy battery and a relatively small oil burner to haul itself around.