My son has been playing on my pc from time to time as he waits fro xbox360 on Tuesday and he really wanted to regen so I told him go ahead. It's a pain unlocking everything again so think this will be a 1 time deal, going to just focus on achievements this time around. Back to level 26 already after a few hours which the xp boost doesn't really help as much as the experience and familiarity of the maps which allows you to get a lot of xp per round.