Well for pvp 5 rogues wont be any easier than 5 dk's, I would say get to 79 than bg for a while with them and try them out, don't test them at 80 because all the deadly geared or better players will make you never wanna pvp again, I always stop 1 level before max and grind honor, usually once I have enough honor to buy 3 or more pieces of epics ill let myself hit 80. Back in BC i bought my entire S1 set including weapons before i hit 70 lol.