What should I get? 9mm, .40S&W, .45 ACP, .45GAP? Glock? Springfield XD? any other manufacturer? The guy at the store today nearly talked me into an XD, I went in wanting a Glock but after firing the two I really really really like the XD. I want a Glock (75% of LE agencies can't be wrong) but the Springfield seems to be a really good gun. I want something full-size (15+ round mags), easily modified (laser, new sights, etc.) and reliable. I also want to go with a large caliber... 9mm is a little smaller than I'm interested in. I've already got a .40 so I'm thinking .45, and I'm wondering if anyone has any input on the difference between the ACP and GAP. Thanks in advance.