Not so sure, the mechanicals on the new +8 are well developed from the aero series, its only the bodywork that's substantially changing.
Unlike the 3 wheeler which was a ground up job, with plenty of R&D and development needed.
I wouldn't have thought MMC would have be brave enough to pass the car onto a motoring journo if they didn't feel it was ready. Contrast this in that it was some time after the launch of the 3 wheeler before anyone from the motoring press got anywhere near the 3 wheeler.
Only time will tell.