I currently two box, haven't been going for that long either...but I have two views:

1) Dual Boxing is tough enough, I couldn't imagine 5 boxing. So I want to stay with just two...maybe 3.

2) The whole point of me wanting to multibox was to be able to run through instances by myself. So 2-3 boxing just doesn't cut it, so I want to upgrade to 5.

I'm so torn.