Truth be told, none of the available engine options could be considered a poor choice by any means. The diesel engines are relatively quiet, flexible and economical, while the six-cylinder 340i is a powerful, responsive and gratifying option.
It's only the four-cylinder petrols that will potentially leave you wanting. Unless you're a low mileage user, and despite being moderately powerful and quiet, there's little justification in opting for one over one of the four-cylinder diesels. The diesel GTs hold their value better, use less fuel and offer more low-down torque.
Consequently its the diesel options, in particular the 318d and the 320d, that will be most appealing to customers - even more so if they're business users.
There was a time – and it wasn’t that long ago – when a diesel that took less than 10 seconds to sprint from 0-60mph would have been considered perky. Diesels aren’t renowned for their standing-start acceleration, after all.
But that was before the arrival of cars like the BMW 335d, which, even with an automatic gearbox, can do the same thing in 5.5sec. So the fact that the 318d GT wants 9.5sec to get to 60mph is bordering on a disappointment these days.