My last 300mls experience: Wow! Day and night difference. I'm currently on Falken 439 M+S 225/55/16 tyres all round (had 16" BBS rims with 34 offset from my E46 nobody wanted.. Doesn't look bad at all though and has 1/4" clearance with front calipers). Performance in snow/sleet is amazing compared to 18" M-sport RFT Bridgestones. I have a short 10-15 degree slope going up to my garage. On summer tyres I sometimes manage if i can accelerate from my across the road's neighbour's (free) drive way. On these i just go up without the wheelspin indicator coming on.
225/55 is one size up from std recommended tyres. It ought to be 225/50. I took these since they were cheap (€340 thru internet for the 4, ok free fitting and balancing for me) and wanted to be sure i could go up one size more (fills the wheel arches better and get more suspension in the tyres) on the more expensive summer tyres too.