Thanks guys... I forgot the most important picture:
and it looks good with the roof up too IMHO
But after a quick joyride on Sunday, I can say with absolute certainty that the 335i Coupe is quicker... at least up to 150km/hr or so... but this thing sounds monstrous and is a far more engaging drive. The 335i is smooth, quick but uneventful. This thing is EPIC, even if it's marginally slower at highveld altitudes, it puts a much bigger smile on your face.
Overall I am pleased and can confidently call this an upgrade, speed certainly isn't everything.