I have had my Crossbreed for several weeks now. I love the functionality and comfort of the Super Tuck Deluxe - comes up just a little short on the clips - so I replaced them with some from another vendor. I use the Crossbreed for my Glock. I was looking for an IWB for my Kel-Tec PF9 and at the time Mark was not producing one for the PF9. So I went with the C.T.A.C. from Comp-Tac. It did not take me long to realize the CTAC would not work for me. The lack of any type of backing wreaks havoc on the skin. It concealed fine - just not comfortable. So I emailed them and they suggested the MTAC for which they just started making a PF9 version. So I opted for that. I just got it in today. The holster is well crafted; it has two pieces of leather. The 2nd piece is to cover up the hardware/items that make the MTAC shells interchangeable. The fact that I can have interchangeable shells for different guns could be a plus. But down to the hard facts. It is bulkier than the Crossbreed. Carry position is limited because the MTAC is not that flexible. I first thought I would have to break it in - but you will sacrifice some in flexibility with the MTAC due to the interchangeability feature. It's not a huge issue except for those that like to carry at 3:00 or 3:30. Once you venture past these carry points the flexibility issue becomes moot. Clips - I ordered this MTAC with the standard and a set of Velcro clips. The standard clips on the MTAC function a little better than the full or oval clips that came with the Crossbreed. Comfort - The Crossbreed wins out here. Maybe the MTAC might become more comfortable over time (break in), the extra thickness = less comfort. Over all I give the MTAC a B+ and the Super Tuck Deluxe an A. Both stand behind their products with an initial return period - Crossbreed even credits the shipping. Comp-Tac has excellent order status updates. In my opinion you will be ok with either one - but for me I would have rather had another CB super tuck. Oh well, I have a few more pistols in need of a holster.