UMP is a smg that use 9mm ammo type. UMP has low recoil and with the help of some attachments UMP will has even less recoil when it equip. Using UMP for pushing compund or holding enemy position is really good because of it fast bullet projectile and for early landing against no vest enemies target.
Tommy gun is a type of smg that use .45acp ammo types. Tommy gun can't attach any scope. Bullet projectile is lower then Vector but is dose better damage. With the shortage of sight the is hard for long range and it's only prefer to close range.