Let me try to answer this from the perspective of going from a M3 sedan to M5, which is slightly different from my case with the coupe. The M5 as i always tell people, can be boring at times if u forget what u are driving. In my day to day commute with it in D2 (middle setting) auto mode in traffic, it's super comfortable and responsive. I always drive with throttle and steering in Sports plus mode and suspension in Sports mode for the most part. This can become boring after a while. I often need to remind myself, find an early morning or late nite, drive it in manual mode, and let it rip. The combination of hard charging acceleration, late braking, and fast cornering is mind boggling in a car this size. The way the fella handles defies physics much more than the more athletic E92 M3. From E90 M3 to the F10 M5, u are gonna get the followings:
- much more straight line speed esp on NS highway (no comparison)
- more responsive pick up so long as your rev is above 2k rpm
- much better interior build quality
- equipment wise, the only major addition is the HUD over the E90 unless u like the soft close doors. The other minor additions i don't really care for
- more space esp width and boot
U loose:
- the S65 music!!!
- manoeuvrability in some tight spaces
In summary, the M5 alternates much more between being gentlemanly and lunatic compared to the M3. I alternate between the 2 cars almost equally. I visit the fuel pump in both cars at most 2 days apart on each top up, so pretty equal attention. Which do i enjoy more? There is no definitive answer I'm afraid. I like them both. The M3 is definitely the more outwardly sporty one and is also sharper. The no. 1 factor that draws me to the M3 is the marvelous S65 V8. I can't get enough of it. The race to the redline is something i used to bitch about when commuting, but these days, i just set it to D5 when commuting and let the brilliant DCT does it magic. Only when i am out for a spin do i drive in manual mode. These are 2 really great cars I must say. Had it not been for the fact that the M3 is NA, i prob won't keep both in the family. If u do not need more space and comfort, i say wait for the next M3 sedan. It is in essence, the current M5 minus the fats and girth. If your taste has matured and would like to move on with something a little more executive, u can't go wrong with the M5
