I have a few of each and can honestly say I love them both. My glock 22 in .40 is my preferred gun as I have spent the most time shooting it. That is what I usually carry.
I have 2 xd 9mm, one full size and one sub compact. The fullsize is awesome and very accurate. I prefer the .40 for stopping power. The sub compact is worthless unless you are shooting at something 10ft away. So, for a carry gun it is perfect.
If you would like to shoot them we can arrange to meet at Blackwing sometime as it is 5 minutes from my house.
-Marc