The UMP is the best. ownage! the red dot sight also helps a lot.

Yep. Best gun evar! Well... in my opinion. I guess the sub-sonic ACP round isn't that great...
Well, it is considered the replacement for the MP5, and not many guns can claim that.
However, I have a feeling it's going to be replaced by guns like the Kriss Vektor and more 'modern' weapons, but I still like it anyway.

The red dot sight helps with zooming in and whatnot.