FWIW, I've heard mixed reviews about the reliability of XDs.
I've heard little to no question on the reliability of Glocks.
Try as many different guns as you can, pick something you feel comfortable shooting, carrying, and have faith in it's working.
The best gun for somebody else may not be what's best for you, however, there is something to the fact that Glocks are the choice for many, many people. Also remember that you can conceal damn near any handgun out there if you're willing to dress based on your need to conceal.