The Springfield is a better gun than the Glock. The XD line rivals H&K in quality at a lower price. My favorite pistol that I've shot was a Kimber 1911 .45...but they're bank. I might be picking up an XD in the future, just don't know if I'm going to go .45 or 9mm. I haven't liked the feel of the Glocks that I have shot before. They are by no means bad guns, but they aren't as good as the Springfields. If you liked the way the XD felt and shot, then that's the one you should get.

Don't worry about the slide release being on the wrong side, it's not a huge deal. Being left handed sucks when it comes to shotguns though.