As some other people have suggested, it's better with friends but not so great playing with random people online. The lack of any real system of sharing loot - bear in mind that acquiring loot is pretty much the main attraction here - means that you could encounter people who just selfishly grab all of the best guns, shields etc before you get a chance.
Having said that, playing through solo is most certainly a repetitive experience and you should expect a lot of MMO-style fetch-quest missions. Personally I enjoyed the game alone because of the wide range of weapons and because the core shooting mechanics feel so precise, but I can understand that some people might find it quite boring without co-op.
Having said that, playing through solo is most certainly a repetitive experience and you should expect a lot of MMO-style fetch-quest missions. Personally I enjoyed the game alone because of the wide range of weapons and because the core shooting mechanics feel so precise, but I can understand that some people might find it quite boring without co-op.