I personally would buy a glock 30 which is chambered for the .45 ACP. I bought the glock 27 which is chambered for the .40 I have shot thousands of rounds through my glocks and never once had any sort of misfire/fail to feed/stovepipe. Also to be realistic if you decide to carry a revolver what are the odds you will also be carrying speedloaders? Sorry to get off track so my opinion is .45ACP, .40 Cal, then .357 Sig
p.s. after you decide which gun to get throw some Trijicon night sights on it youll be glad you did.