Apologies if this is a re-post but couldn't see any mention of it. Chris Harris drives the E63 4Matic: Driven: Mercedes-Benz E63 AMG 4Matic - PistonHeads I was never that interested in a 4WD Merc. What's wrong with RWD However, I didn't realise the E63's system is RWD biased. I like the sound of it a lot having read that review. And having driven an E63 on damp tarmac at MB World I can see why 4WD would be useful on the road. I like the sound of the A45s 4WD system too. According to Car magazine it sends power to the rear wheels when it detects you're having fun rather than waiting for the front wheel to lose traction as most other front biased 4WD systems do I thought I'd heard MB we're going to offer some E classes with 4WD. Did I imagine that or get confused with BMW? Anyway, enjoy the Harris's review.