The Mercedes E-Class is very well equipped and available with a great range of engines, from efficient diesels, to tax-friendly plug-in hybrids and punchy petrols. It's pretty quiet and comfortable on the motorway, too, but the ride could be better around town and, while the boot is big, the rear passenger compartment isn't, relative to its rivals. Overall, the BMW 5 Series is a better car to drive, has a better infotainment system and is better built inside.