As has been mentioned, both guns will work. The revolver presents some challenges but nothing serious. Having speed loaders and speed loader carriers is the challenge. Not all COF are revolver neutral... but you are only compeating against other revolvers so that is not as big a deal.
The Kimber should hold you in good stead, I shoot two different Kimbers myself. Two mags will be ok. Where the challenge will be is if the local club has more than one stage per bay. Here in central Texas, we tend to stay hot and move directly from one stange in a bay to the second one. This would mean you might need 4 mags. Most of the time, we help new shooters with only a couple of mags by reloading mags for them between strings.
The most important thing I can tell you is this... Be Safe... and HAVE FUN!!! I see this as my NUMBER ONE JOB as a Safety Officer; to make sure you do both. If you also learn about being tactical, great. If you win, way freaking cool! But having fun is what this is all about.
Have a great time and let us know how you do.
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Bubba
IDPA# A04739
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It is long been a principal of ours that one is no more armed because he has possession of a firearm than he is a musician because he owns a piano. There is no point in having a gun if you are not capable of using it skillfully. - Jeff Cooper