Looking at it from two sides, business and shooter, here's how I see it. The Smith and the Glock are less expensive otherwise my local PD wouldn't be carrying Glocks, and I wouldn't own a Smith. The Glock has a long proven record of reliability. The Smith is new, but except for the mag issues should be as reliable. The mag release issue doesn't even require an armourer to fix (get some spares thrown in with the deal) and the mag issue can be fixed using the all steel mags (you should be okay to get those). The Smith can be made to fit anyones hand, the Glock requires practice for many people to shoot well due to it's grip size/shape. The trigger on the Glock is on average not as good as the Smith. The Smith has a magazine safety - I know people hate these but they can save your *ss if you're in close and wrestling for control with a meth freak, just pop the mag and give the gun to him, and while he's trying to figure things out kick his sorry *ss. The Smith is safer to strip, no trigger pulling involved. The Smith is ambidextrous, the Glock less so. I have no experience with the Sig Pro, the Springfield (how's the QC with those?), I would only give a Beretta to people with really big hands, who I didn't like much. The Walther has something of an accuracy issue (this second hand) and is quite costly. Thanks for opening this up, it really makes for an interesting exercise - but I'm glad I don't have to do it for real.
PS. Is the switch necessary at all, are your guys (gals) capable of "max-performing" a revolver? - and would they be as well served with an 8 shot revolver? I say this because the RCMP sited 'firepower disparity' without ever training staff to use speedloaders, never mind speed loading.