I've got the Michelins on my car, put them on last October. The moment I drove the car after putting them on, I could immediately tell that they were slower. My 0-60 time is slower, the amount of gas I need to use is higher, and as a result my MPG average has dropped rather considerably. If I had to guess, I'm probably averaging a couple MPG less than I was with the old tires. My car is a non-turbo Subaru, so it's not like I had extra power to spare before putting the tires on. So that's my biggest complaint about the tires.
On the plus side, handling has been good, braking is good, I've had no problems with them in the rain, and on smooth surfaces they're very soft and quiet. However, on concrete with series of horizontal grooves in the road, they have a very loud whirl sound. It reminds me of a jet engine if you adjust your speed, because you can hear it spool up and down along with your speed.
I was upset with the tire because of the loss of power, but then I got to drive them in snow and ice, and that was the saving grace of the tire. I drove on ice without issue (obviously you can't be stupid, but the car was able to drive without a hint of hesitation to get started). I've driven through heavy slushy roads without feeling anything different. Then about a month ago we got 8+ inches of snow, and I drove though that with ease. That was vastly different than the stock tires which wanted to have the back end slip out every time you took a turn.
Ultimately, I wish I had gone with the Continental tires, but the good winter performance saves me from being disappointed with my purchase.
If you live in an area where dedicated winter tires don't make sense, and you're willing to give up a little bit of power/MPG, then the Michelins will serve you well. If however you're not willing to give up any power/MPG, then I suggest trying the Pirellis.
