I love my Smartcarry. They know how to conceal! I don't use it with my C9, but I have tried it out and I don't feel much of a difference in the carry and concealment part except for the weight of the C9 and some difficulty bending at the waist to tie my shoes. My smaller SKYY 9mm slips in fine and rests low so I can bend easier, but the C9 protrudes out into the top of my stomach -- I guess if my belly was a bit slimmer that wouldn't matter.
When you order your Smartcarry, order it for the largest firearm you're going to carry. Small guns will fit in a larger Smartcarry holster, but big guns will not fit into a small
