Seconding Chris in Va, the XD and XDm series have a slight safety advantage over the Glocks because of the grip safety. Less likely to go off just from something contacting the trigger. I consider the XDs to be safe in softer fanny packs and other modes of carry as a result of this feature also. Glocks you need a holster that is hard-sided on BOTH sides of the trigger area.
But if you are holstering either gun with your finger ON the trigger, you are in big trouble....
I also second the advice to take a safety course FIRST.