I also use the MTAC for carry. The knockoff verious are often cheaper, however they do not conceal as well. At least not with a tucked shirt. Giant clips are a dead give away that something is missing as they are out of place. Sure black clips on black pants with black belt helps, but it still stands out.
I currently use the C-clips so you only see a little on the top and bottom of the belt. I may have to check out the velcro clips though!
I started with the Standard, then went to the C-Clips and finally the velcro, it took a bit to find that sweet spot to leave them in but once i did only someone staring at my rear/side from about a foot away can tell i have it, and im a pretty skinny guy at 6' and 160lbs.