To me, it's hard to pick which tag team move would be the greatest finisher ever. I guess the obvious choice would be the Doomsday Device, but to me, it was always kind of boring. Effective, but boring. The 3D is up there, but really, I was never that huge of a fan of that one either. I was always partial to the Hart Attack. It wasn't as flashy as the 3D, or even the Doomsday Device, but to me.. It was the better finisher. It was quick to hit, didn't take a whole lot of set up time.. Which to me, made it more effective. With the Doomsday Device, more things could go wrong. So, simply by the quickness in which the move could be delivered, makes it the better finisher. So, I guess I'll go with the Hart Attack on this one.
Though, I will say that the Motor City Machine Guns probably have some of the better tag team moves/finishers of this generation. In a couple years, a lot of their stuff could be be listed as the best finisher(s) of all time. But, that's just my opinion.