I seriously doubt that the ///M can give you the same comfort levels with a spare wheel :roflol:
As Sash has said, you haven't heard my baby purr as yet :rollsmile:
The 550i power is almost the same at the E39 M5 and with my Auto, I have killed many other so called fast boys on the road. It's certainly no sloth and handling is very underestimated. Yeah, it's not an ///M but I believe that you will enjoy it more as a daily.
It actually handles better than my E90 330i which was running Koni suspension on similar sized tyres. If you plan on hitting the track, then this car isn't for you.
Parts on the other hand is most likely going to be worse than the ///M cos there is almost nothing in the spare shops. I had to buy an oil filter from the agents which tells you something.
Good luck with your choice :thumbs: