I have the CTAC by COMP Tac and love it!
The only problem with the CTAC is you have to wear an under shirt under the holster cause the kydex is uncomfortable next to your skin.
I carry a full size 1911 often, with a shirt tucked over it and it is barely noticable, and very comfortable. I dont even know it's there most of the time.
They have awesome service. I broke my clips 1 month past the warranty and they replaced them at no charge, and didn't charge for shipping.
My last Gunsite instructor swore by the CTAC holster.
I spoke with a very knowledgable person there and he said the c-clip is worthless. The V-clip with the velcro is the best if you don't change belts often, because you have to put velcro on each belt. I use the standard clips and love them due to the awesome range of adjustment. But, they to tend to travel around my belt, moving from my side to the midel of my back thru the day. That's why I think the velcro would be good.
If I wanted a leather backed model (dont have to wear an undershirt under the holster), like the MTAC, i would look at the "Tucker" "the Answer", I have been told it is a superior design to the comp-tac.
IMO the key to comfortable carry is a heavy reinforced belt! Standard belts suck, no matter how nice the holster.
http://511tactical.com/index.asp?dept=61&number=59405