Glocks only fire 17 rounds, and its Extremely accurate, and semi-automatic, not full auto.
And a Thompson may not be accurate, but can fire up to 30 rounds.
I really wouldn't know anything about the ammo capacity, but what about the Glock 18? It was fully automatic, and I would have thought that it would have had more rounds from that.
No, I didn't get this from MW2, I just really like the shape of Glock's and that caused some interest in some of there guns.