I just got the KSC and I love it. Haven't gamed it yet, But Im really digging the metal Slide and over all quality. I had a choice between the two and picked KSC after a lot of research and asking a few people of their opinions as well. It sounds like both are great pistols, I don't think you could go wrong with either.
Maybe you should get AV'd before worrying about which side arm to pick up...