This is my fifth BMW and third M car. First M5. Ive had 3 series, M3, M5 and now I also have a 750Li. I don't expect any comfort for a M car but this is harsh, Too harsh. It is not right for everyday car but I've seen M5s in NYC streets. I can not imagine driving them in NYC. I live in Los Angeles where streets are little better than NYC. The performance is excellent however I do not know if it is worth more than the E90 M3, I never owned but driven a few times. The quality is terrible. I had more mechanical trouble with this car in last few month than I had with all BMWs in last ten years. I became close friends with my dealership's chief mechanic.
Have used my friends for a month (we traded I have an M3) and it's a great car! So many complaints from critics, but the trick is that you really have to tinker with the settings first. Everything is programmable. Set the M mode to everything power and it's frighteningly fast.
For people who complain about the stability control not being able to fully disengage, you're testing the car in a controlled environment. In a real world setting, a car with this much power and this much mass needs it to be on. Steering is a bit numb however.
Sound system and idrive are a big upgrade. Styling is still understated. Seats are very comfortable. Overall great car, but still love my M3.