Payday is a lot more addictive coop-wise than BL2 is, in my opinion. Great little game.
Aside from both being shooters, they're very different games. Borderlands is a FPS/RPG mix and would probably be more of a long-term investment if you intend to play coop with your friend. The GOTY edition has a ton of content in it as well.
Payday is a decent game, but best played now and then rather than for an extended amount of time. I've had fun playing it with friends, but it's mostly been a game we hit when we have 15-20 minutes to kill while we are waiting for someone to come online, etc.
I own both games, but only played Payday online a couple times (is difficult to find games with people who don't kick you out because they want a private server but forgot to... meh). Played BL singleplayer only, never online, because don't have friends playing it (and don't want to pay for BL2 before finishing/going online with BL1)
RE: Borderlands or Payday
Payday pretty much needs to be played with 4 people. You can have more fun with just 2 in Borderlands, though it's ideal with 4.
I'd have to disagree. Things just become sort of a snafu with 4 players, especially if they're playing "lone wolf" style.
I think the difficulty and playability are their most balanced with 2 players.
I really don't think there are many people that would say playing Payday with 2 braindead bots all the time is the ideal solution, but hey, more power to you. There are so many situations in the game that work much better if you have more than 2 lines of site covering different areas.
Err, I was replying to this:
"You can have more fun with just 2 in Borderlands, though it's ideal with 4."
I was talking about Borderlands 1/2, not PayDay.
I think I will go with BL... want to try if the MP is as fun as everybody said...
Someone go start a payday cag group.
Let's rule the world!
Thanks for the answers!