BUT.. I will say that a P90 is my favorite "backup" in Rainbow Six Vegas 2. And even there it has crap penetration.
Crap penetration?
Check out post #86 of this thread (cannot link image directly as apparently it is a private album):
http://forum.pafoa.org/showthread.php?t=147999&page=9
There is a reason this specific caliber is used to Protect POTUS and the Queen of England.