Great thing about our department is that we get the opportunity to go to the range and fire rounds on target with our H&K .45's....good prep for the police academy and it will also give me an idea as to how the pistol grip feels in my hand....they make a nice compact H&K 45 ..so let's see how it goes.
Late to the party, I know.......My CC is an XD45C. It's an excellent firearm. If I have a complaint, it'd be that the trigger squeeze is rather long. I own one because it fits my hand the best and the only problems I've had is stovepiping due to my own "limp-wristed" nature after a couple of hours of constant shooting. I keep a CT grip on mine and pierce extensions for the short 10-rnd magazines. It conceals well on my 215#, 5'10" broad-shouldered frame.
It has NEVER failed to fire on me when it wasn't directly my fault. With the CT grip it feels very natural to shoot.
If you're in the market for a handgun, the XDs are an excellent choice, especially for the prices. In the end, try a few out and go with the one that fits your hand the best.
As far as caliber, the three common cals punch holes with almost equal efficiency, so go with the largest one you can comfortably handle. Lean towards the cal that your department uses, for ammunition's sake. I'm sure you know that you want your firearm to be natural. If you need it, you don't want to be thinking about how to operate it.