I've owned the XD in a .45 tactical, .45 Service, .45 compact, 9mm tactical and 9mm SC.
My favorite is easily the .45 service model.
The XD's are super relaible. My daily carry gun has around 7,000 rounds through it. It's rock solid.
Send your XD in to Scott at Springer Precision for a carry trigger, new sights and a couple of other things and you've got a really sweet machine.