That is fairly easy for me:
1) 1911 full size
2) Kahr K40 Elite 98
3) Glock 23
Now that is assuming my choices were limited to those particular models. Given a little bit of variation though, I would pick:
1) Kimber Classic Stainless full-size .45 ACP
2) Glock 19 9mm
3) Kahr MK9 Elite 98 9mm
I am not a fan of the .40 S&W cartridge. I don't like the extremely high pressures it operates at. I also think it is a redundant cartridge, not offering me anything not already covered by the .45 and 9mm, both of which have a superb historical century old track record. I am a die hard 1911 .45 ACP man. In the full-size fighting pistol, it has no equal, and the Kimber is the best of the breed. I think the Glock 19 has few equals in its class, offering excellent firepower in a compact package, but only if pre-ban mags are available. The Kahr is a superb gun, but I would opt for the MK series if I already had a mid-sized Glock. The Kahr MK fits on the ankle as good or better than a 5-shot .38 and much better than a Kahr K series. The USP has an absolutely horrific double action trigger pull. The P7 is a very proprietary and very expensive gun. The Sig P232 is chambered for a substandard cartridge.