I have four accounts but the only time all four are in game together is for an instance or when I need my warlock to summon one of my alts. I play one, two or three at a time depending on what I want to do. I started multi-boxing in order to be independent. I play at odd times and like to be able to log in and out as I please. I see no reason to step up to five accounts since four are accomplishing everything I want to do.