IMO, the Glock can take more punishment. However, I really enjoyed some time I spent with a .45 ACP XD. When I go shooting, and someone does not like my Glock, I suggest the XD. I don't know why I did not like the 9mm XD M. 19 + 1 is a lot of capacity.
The grip of the 9, 40, & 357 on the Glock is a little smaller then the 45 & 10mm. I don't like the grip on the 9mm XDM. I was really impressed how easily I could control the .45 XD, and it could be the grip difference between the .45 XD and Glock. But if your going to get a .45, get a 1911 :).