Even as a run and gunner, dog tags are terrible. You kill an enemy or two, then are FORCED to run into that area to collect the dog tags. What if you killed them in an area where there are like five people where they were holding down the area? You're never getting those tags unless you run into their area and get mowed down.
I can't wait to get retriever and don't have to deal with this system that FORCES you to let enemies get free shots on you. It's still stupid that I have to give up a module for it.
I had a game on statue where I killed at least 7-9 people in one life at the very beginning of the game, but couldn't get the tags because they'd come back for revenge before I could get them all.
Also, the lag is terrible. If you don't get a good host, you might as well just leave since it will take 20 bullets to kill someone without armor on, but you take 2 to kill.