I LOVE IT!!!
It's completely adjustable. I spent about the first week adjusting it to the point that it is very comfortable now.
I can't say that I forget that it is there, but I can say that it doesn't bother me, or restrict my motion. (at least not to bad, I haven't tried, but I'm sure it would impede a Karate style side-kick, but if it got to that point, I probably should have drawn and fired)
Also, with the MTAC, you can buy additional Kydex holster frames for your other guns. So keep the leather and attach the proper Kydex frame for your carry-of-the-day.
I did have to buy larger sized shirts, but I was able to keep my current sized pants, I do need to get a new belt though.
You just can't go wrong with the MTAC... IMHO