I would suggest it. I don't ever play it solo, but it is a ton of fun to go in and derp around with your friends. There is some disparity between the bladed melee weapons (katana, axe) and the guns in regards to their damage output though. The blades are ridiculously strong against the normal infected (probably 90% of the enemies you encounter), so expect there to be some competition for those if they pop up. Again, I only really play it to derp around with friends so it's not a huge deal to my little team.
I can't comment on the PvP side of things. Only ever done the co-op PvE. I've heard it's fun though.
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