I'm still digging it. Scavenger replacing launcher and grenade ammo really allows you to play a support role. If I know I'm gonna hole up in a room, I'll stick with the last shotgun unlock, I'll also use the m27 for range.
Maps are kinda awesome in that you can really play any style you want, close or long.
I can count on Slums being at least a 30-8 for me - people can't stay out of the house. I throw 2 bettys, and every shotgun kill gets me another one to throw. If I get a sentry gun or a guardian the shit goes down.
Also, I got a care package throwing 1 EMP grenade today, it blew up a sentry, a guardian, 2 claymores and 3 shock charges all at once. I also ended up getting 3 EMP assists out of it