The 552's fire rate is VERY slow, but it is a VERY powerful gun.
I personally think the right person could take out someone skilled with an I-Dub, with a 552.
You've got to know what to do with certain guns, and how to control every aspect of the gun. The 552 is deadly up close.. i mean land about 1/4 of a clip into them and they'll fall.. trust me.