First of all, since you are from Oklahoma, welcome! I will be neighborly and try to help you out here. I personally do not own a XD myself and there are plenty of members here that do. They should be along to give you their opinions and experiences shortly. I have shot a few and the grip safety on the XD was no problem at all.
If you have a grip that is in any way correct you won't have to worry about the XD grip safety. The ergonomics of the firearm make the safety a natural part of the grip, so you do not need to adjust your grip. I am sure when you finally get to shoot it, you will find it very likable. The 40 is a good choice, reliable, ammo is plentiful around here, shoot it, use it, enjoy it, and maybe eventually work your way up to the.45 XD.
If there was a problem with the grip safety interfering, it wouldn't be such a popular pistol.