I play it single player because I don't have time to find the right server. Besides I get better frame rate playing it single player.
The big difference playing it single player is that you are truly on your own and no bandits trying to kill you to steal your stuff.
I don't particularly understand why that guy doesn't want a single player version.
A new version of the single player mod is out fixing a problem with the "HUD" disappearing after resuming a game.
http://kronzky.info/missions/arma/dayzsp/