I agree about the dogs. My friends and I are pretty annoyed by them. There have been multiple times where I've unloaded a whole clip to the dogs face and he still runs right at me and kills me. I've seen dogs get shot before, Riley is on steroids or something.
Riot shield or ballistic vests work fine.
However I do admit that Guard Dogs make Squad Assault very easy, especially on small maps.
If your entire squad has the hardline perk, ONLY the guard dog killstreak selected, and uses sub-machine guns.......lol.
You can basically sit back & the dogs will do all the work, not much fun.