I have 2 unneutered boars here and they are great together. The trick is to have their ages spread out and knowing their personalities. I got Stryder at 1 year of age so when I got him a buddy I got Callaway when he was a couple of months old. This way Cal was a baby and would respect Stryrder until the adolescent hormones kicked in.
Cal tries to be dominant pig every so often but Stryder says no to that.
Pigs have to find their own pecking in ordering in their pack. There maybe some noise and small fights, but as long as it is not blood shed then you are alright.