As far as motors, an E30 M3 is a great drive regardless of motor. I've driven S50,S52, and S65 swap cars, stock and 2.5l with all sorts of cam setups and they all are great.
I absolutely I prefer a 2.5L S14 as my favorite; however. Add a carbon airbox and the sound is just amazing and far better than the S54 in my opinion.
I actually had the parts for an S54 swap with 6 speed and alpha N ready to go into a track rat but then sold it all and got my 1M.
Love my 1M but I sure wish I also had an E30 M3.
