I know this is a bit of a zombie thread, but I didn't feel like typing everything up again, so a reply seemed the easiest way to go.
At this point I've been carrying (and shooting as often as I can get ammo) my XDs for a few months, and like it even more than I did when I bought it. Not a single failure, and still far more accurate than any of my other CC guns. With the Peirce extension it shoots like a much bigger gun.
The biggest advantage is - obviously - it's size. I carry it at about 5:00, and even when I'm sitting down I could nearly forget it's there. I do still need to upgrade to a better holster, so I imagine it's carriability (lets pretend that's a word) will only improve.
I did wind up changing out the springs with the powder river kit. It took some time, but seems to have marginally improved the already serviceable trigger. I also added a powder river rubber grip decal thing. It was very cheap, and makes the grip a little more "sticky" without adding anything in the way of bulk - I highly recommend it.
Lastly I did wind up installing Trijicon night sights. They were something of a bear to do, but less of bear than driving an hour or so to have a gunsmith do it. Lots of lube and some time in the freezer did the trick.
Anyway, if you're in the market for an awesome gun, I highly recommend this one.