I have 4 XD Pistols. 2 XD40 Service in Olive Drab/Khaki, 1 XD45 Tactical Compact in Khaki, and one bitone XD45 Service. All of them are excellent pistols and I have put a lot of rounds thru all of them without any issues. I also have a Glock 9mm, and I like the dual safety setup on the XD (some XD's also had a safety on the slide) vs the single trigger safety on the Glocks. There are a lot of aftermarket parts for them from recoil springs to trigger kits.
I honestly shoot the XD45 Tactical Compact the best with the 10rd mag and pearse grip extension. It fits perfectly in my hand.
My friend has an H&K 45 and I find it to bulky. Some people swear by pistols with hammers and then others swear by hammer-less pistols. Also an XD/XDM is extremely easy to tear down and clean. Congrats on your XDM45!