I just downloaded and setup five accounts for Vanguard. Free 14 day trial. I figured I might as well check it out again.

So far (I am only L5 =)), I'd say it's likely to be much harder to multibox than WoW. Partially due to the lack of addons (although, I haven't done much research as of yet..maybe there are some good ones around) and the macro system. Looks like a lot of quests don't update the entire group either (e.g., whenver you have to interact with the enviroment to complete X tasks). It might just get too tedious for me to do 5, I think at most I would end up doing 3 since I have three computers.

It seems like anyone who boxes in Vanguard, usually just dual box. Although, IMO it's not really even dual boxing, it's just running two accounts from two computers and using one toon to buff (i.e., buffbot).