How great the game also may be in co-op always - I look at gaming as time for myself, where I can do at my own pace without stress what I want. That's why I play alone, and Borderlands 2 is a pure co-op game. Sure, real-rested veterans will make it alone, (to show several YouTube videos that) with a lot of anger and frustration, but for the casual gamer who just wants to have some fun easy, Borderlands 2 is unplayable. Opponents from all sides at the same time that appear out of nowhere and at the same level much too strong, embitter every game. By Borderlands 1 I'm almost through marches and rarely died, but here I'm in the very first few missions over a dozen times the bucket.
Unfortunately I was not forewarned, because most match reports related only to the co-op, even the majority of reviews by players. So I want the other Casual Gamers warning here: The game is too hard for us. I feel cheated directly. If there should be a Borderlands 3, I'll scour the reviews under the microscope.