I would like to third that, but I have one more bit.
Subs (not the ones you eat

) are not only good for Urban warfare, but they have their place in other terrains as well. I believe a unit with mixed weapons ranging from subs, the standard long rifle, carbines, etc., preform the best. Even in the woods when you have the enemy at 100+ yards, you can lay down some quick cover fire with a sub to help out your comrade with a Garand or whatever. Even though I am defending the sub right now, and a Thompson sure is a cool weapon, I think if it came down to it, I would prefer to have a Garand in combat over a sub, unless I was hungry.