Ultimately, it "felt better" in my hands.
The Glock felt like I was holding the wrong end of a baseball bat. I did like the XD. I ended up feeling like the DA/SA on the Sig was a bit more familiar having an old Winchester 94 and having shot a bunch of revolvers. The Sig was actually the cheapest at the time and that did have some influence.
Honestly, they are all fine weapons. The Sig only comes with one mag. Extra 10 round mags are pricey and hard to find.