I've had less success with the PDW than the MP7 and vector. I honestly feel that it's not as good as people make it out to be. I started out with the PDW just for the mag size, but have been using the Vector more often - and the MP7 results in an even better success rate than both of them.
Same thing happened in BLOps with the AK-74U and the MP5. For some reason I always felt I did better with the MP5 .
The mp5 was AMAZING in the first black ops. I used extended mags on it. I think he 74u was better though.
I gave more kills with the mp7 then I do with the PDW
There was only one attachment for SMG's in BLOps...Rapid fire! Dual mag was good too though.
If there are two evils, I'll try the one I haven't done yet. Gamer tag: Spinal101