ive got a TM mk23 and i love it, its my primary for cqb, with the p226 for quick action, had ASG/others, and they are nowhere as good, usually 3/4 reloads before re-gassing, i run them on propane, but have carried out the pressure valve mod, but ran for prob nearly a year before it popped, but the ASG mags dont have them and are just as good, ( maybe except the feed lips for some reason.....)
you can get dropleg holsters for them from the bay of E which holds them well even with lam on ( would recommend the cree upgrade for that also) for about £25. there is also a person on another unfriendly forum who makes them with good reviews
i totally agree with R-C-D best all-round sidearm
on a side note i do run mine on 0.28's, helps people notice their hits more......