I think with VTs it depends a lot on the personality (although you could say that for any fish, really)-- I've had very relaxed VTs before, and I've had others that are crazy-active. Currently I have a VT and a HM who have about the same activity level, but the HM has, um.. a wider turning radius.

Unlike most fish who'd be happy to, you know, swim around the whole tank, he often decides he wants to do a 180 degree turn so he can sit on the leaf DIRECTLY BEHIND HIM (as opposed to the fifteen other leaves available), and due to the size of his fins the process will often take a hilariously long amount of time.