I have a comp tac mtac holster and I really like it. Very similar to a crossbreed which my brother has and he really likes his. I can't say one is better than the other.
As it's a IWB, it does it's job but isn't a purdy leather holster like the galco concealable.
+1 on Blackhawk SERPA. But I carry a FS .40 everyday w/a Badge. Off Duty? A new Sheild 9, of course. Fobus PPS paddle or a Uncle Mikes nylon Pancake. Early style. They work really well for nylon, but you can't get long term wear out of them. Nylon comes apart from abrasion.
I have a Crossbreed Supertuck on the way for my M&P9 and have a Serpa holster for the Glock 20/21 that also works for the M&P. That thing is hard to conceal so for now I'm using a DeSantis Speed Scabbard which I find to be a very comfortable OWB holster option.
I'm a bigger guy and not easy on holsters and with 28 years of cc'n the one I have that's held up well and is very comfortable for 6 or 7 years so far is a - Comp-tac Minotaur neutral . The kydex is changeable for many different handguns too . Worked well for me with a kahr tp40 and wifes m&p4.25 core when I had to have a soft shooter.
From Comp-tacs site - http://www.comp-tac.com/images/0403 NewCant blk gun-in ST blk clip front sm.jpg