single or co-op with friends. I wouldn't bother with public co-op.
Agreed. I played the first game co-op with a friend and it was great, since we could go through the story together. I have finished the second game with a couple of characters in single player.
I tried multiplayer co-op with random players in the second game, and found it to be just basically trying to kill bosses and loot items. That is OK, but I think it would be very difficult to find a random group to stick together long enough to finish the story.
BTW, is it just me or is the game harder on all modes since the ultimate vault hunter patch? I know they buffed the enemies for UVH, but it seems like they gave them a lot more health and shields in the other modes as well. I have played a lot and have a pretty good selection of equipment, but in TVH mode now, seems like they do almost no damage sometimes, whereas before I was breezing through the game. Now I can get a critical hit with a pretty good weapon, and it doesnt even bring down the shields sometimes.