Actually it makes more sense to rebuy 4 accounts. You get free months. Currently I have to pay 75 just to play again, add that to the $19x4 for vanilla WOW and then $25x4 for transferring and it is $250ish. For just one group. If I did 2 groups it would go to 350.

So it appears if I plan to level more than one group it makes more sense to buy 4 battle chests + wotlk (4x30 + 4x33 = 252. So you save about 2 dollars if you only plan on leveling one group. Actually you get more by re-buying as you get 1(?) free month for each of the RAFs. So ya I think I will be buying them all over again =/

editx2: now the question is: What server has an active raiding Alliance multiboxer guild?