the 300% xp bonus wont work if you pull your lower toons with a highlevel main.
maybe its faster to level 5 new toons since the 300% increase is a lot.
remember that you can grant a level to a lower toon every 2 levels you make.
which would be 102 level if you hit 70 with all 3 toons in the raf 3 month.. 3 "free" level 60 chars for you