The Mercedes-AMG E63 is a mid-size saloon with a classy cabin and a monster of an engine. It rivals other ‘Jekyll and Hyde’ executive cars such as the BMW M5, Audi RS6 and Jaguar XFR – all of which are about to be replaced by new versions. The regular E-Class looks a bit too classy to carry the AMG badge so this most expensive model gets vast air intakes, swollen wheel arches, menacing black trim and a couple of V8 badges to hint at the monster that lives under the bonnet. While the outside is decidedly more sinister than the regular car, the cabin’s class and sophistication remains. The E63 takes that stylish design and adds a bunch of suitably sporty touches including a flat-bottomed steering wheel, new leather-trimmed sports seats and numerous AMG badges. The 64-colour ambient lighting is standard on the E63 alongside the large infotainment screen that replaces the traditional analogue dials. Passenger space is excellent in the saloon and even better in the Estate thanks to its more upright roofline. Boot space in the saloon is above class average while the estate is among class leaders for capacity. However, you don’t get an AMG model for its practicality, but for the masterpiece of an engine. The E-Class doesn’t disappoint – nestled under the bulging bonnet is a 4.0-litre V8 that can produce up to 604hp in the most-powerful E63 S model. Regular AMG models get a ‘mere’ 563hp – still nothing short of astonishing in a four-door saloon. The E63 is four-wheel drive only, so 0-62mph acceleration times are predictably mind-blowing, completing the sprint in 3.5 seconds. It’s good at taking corners at speed too, making it arguably the most well-rounded AMG model yet. E63 S models also have the ability to disengage the front driven wheels for some good old-fashioned sideways tyre destruction. One thing is certain – the E63 isn’t cheap. However, if you take into account the two infotainment screens, the plethora of autonomous driving systems, the well-made interior and combine them with the impressive pace, you have a well-equipped, practical saloon that can easily challenge a supercar for speed.