Love my XD .40 Service, and am considering a Subcompact 9mm. Reliability-wise, I've had a little trouble with feeding from one of the Clinton mags it came with, but the other 10 rounder and all of my 12 rounders are running great. I have had some surface rust appear after carrying all day and absolutely soaking it with sweat. In regards to the older finish, I will say that the XD needs a bit more attention to upkeep and maintanence than some other pistols. However, the new Melonite, or whatever it's called that they're applying nowdays, is supposed to be much better. I prefer the XD to the Glock I used to have based solely on ergonomics. The XD is just simply better suited to people with average to small hands. The Glock trigger is better, being shorter, a little crisper, and with a far shorter reset. However, the XD trigger is still great. I do long for the Glock's super-short reset though.
Now, the worst thing I can say about the XD is that you cannot buy parts for it from Springfield Armory. If you lose a spring, you must send the entire pistol back to SA for them to work on it. Figure $50 to $60 in shipping, and being without your pistol for 3 weeks or 3 months. It's a stupid policy. But (crossing fingers) I've never needed replacement parts for mine.