If there’s justification in recasting the bigger of BMW’s two GT cars as a 6 Series rather than a 5 Series, it may be that it better prepares you for the fact that, dynamically more than anything else, this remains a luxury car first and foremost rather than some kind of extra-large middleweight executive saloon.
Simply put, as something both to drive and be driven in, the 6 Series GT is at least halfway to a 7 Series limo; probably slightly more than halfway, if you had to be absolutely specific.
Despite its M-Sport-specification 19in alloy wheels and run-flat tyres, our 630d GT test car rode surprisingly well – although not without a little bit of rumble over coarse tarmac, or without a slightly firm, hard edge over sharper lumps and bumps.
The car has Comfort and Comfort+ modes for its air suspension as well as the usual Normal and Sport settings and probably feels most at home in Comfort.
Thus configured, it glides along very smoothly and with excellent long-wave compliance at typical motorway and A-road speeds, but never quite oscillating on its springs or running out of close body control as readily as it can at higher speeds in Comfort+.