I have Glock 22, M&P 9 and Walther P99 in .40. They're all a bit different, that's why I have them all. The P99 is numbered serial, not alpha-numeric so it's made in 02 I think. Made before AS, DAO, QA models. It has a single-double feature and the single's better than Glock and not increasing like the M&P. The new ones are a bit different and the DAO is way harsh by comparrison. The QA is the one I think has the best trigger. I think you can get improved parts for them too, I just can't remember where. The hardest part is to get reasonably priced mags. If you need to, I can put you in touch with an individual that may be able to help.
Is that what you're asking?