Just my $.02, but I shoot my P90 a lot in various competitions, especially in those that are momentum games like that involve bowling pins or pepper poppers. I've out shot a LOT of 1911s in games like that. I shoot it well, one of my favorite guns. I was shooting it in IDPA because I shoot it so well, however, I switched to 9mm in a P85 I got cheap from a guy for two reasons. First, 9mm doesn't recoil as bad, less muzzle flip means quicker double taps and multiple shot strings. Too, I found with my P90, on tac and speed reloads, I had a bad problem with occasionally getting the mag hung on the edge of the mag well. Not an easy way to bevel that mag well. With the tapered 9mm mags, I don't have the problem.
But, for some reason, probably accuracy of the gun, my scores weren't much better with the 9. The trigger on that P90 is just hand over fist better than the P85 and I shoot it so much better, plus the gun shoots 1" 25 yard groups off the bench where that P85 is more like 2.5".
My philosophy on IDPA, though, is shoot what you carry. If you only care about being competitive, Glock seems to be way to go. That's what most people shoot. But, I was shooting expert with my P85 and P90 when I quit. I don't carry Glocks. I think you can do well with the P90. If I ever get back into it, I may try to bevel the mag well best I can and try the P90 again. I can deal with the .45's muzzle flip, but that hangin' the mag on reloads thing really miffs me off.
