You ever shoot a gun with a can on it? The slim ones IMHO are very rare, most of the cans I've shot are pretty thick in DIA.
If you have never got a chance to be around supressors (very few actually "silence" a weapon) and are on the west side, go to Wade's East Side gunshop in Bellvue on Bel-Red road. They sell supressors, and I plan on going through them when I pick up a can for my P22.
I always thought a supressor, for real "James Bond" work on anything bigger than a .380 was pretty funny, most black-ops suppressed pistols are .22s, and have been since before WWII. I've even heard stories that the SEALs carry a supressed .22LR upper for their AR15s for ultra-quiet work. But thats getting a bit OT.