Which forum software has the best modifications?

[Quilceda]

I've run one fairly successful PhpBB board and dabbled a little bit with SMF, but I've never used vBulletin due to the cost involved. I'm thinking of switching, but I want to make sure it's the right decision for me. One of my highest priorities with forum software concerns the quantity and variety of mods available.

I was satisfied with the mods available to PhpBB users, and I'm wondering if vBulletin has an equally good or better selection. Has anyone used many mods from both?