we have 2 boys...
we adopted Roscoe when Remy was one year old-both were neutered, and after 2-3 days of squabbling and getting used to each other they are now inseperable. Every once in awhile they will get upset with each other over a bone or a toy, but nine times out of ten they are best buddies! You should expect an 'adjustment' phase but after that you should be fine
I know that a lot depends on the personalities of the dogs, too!
have fun & keep us posted!