I've been a Glockman for about 13 years. I've carried a G27 (.40) for almost that long. I also owned a G26. Now a M&P9c fills my holster and I'm really liking this gun. It carries about the same, can't really tell the difference in that department. It just feels better than the Glock in my hand and seems to be a bit more accurate. Holsters, still seem to be on the scarce side. My ankle holster for the G27 works for the M&P just fine. I've got a Blade-Tech belt/paddle holster on order, but it's for the fullsize. No compact yet from them. Also ordered a Mistersofty IWB, should get it Thursday.
Time will tell on the M&P, as to their reliability and longevity. The Glock has been proven in both of those departments. The thing I like most is the M&P is made by an American company and by purchasing it I'm helping the American gun industry.