Keep in mind that, while the static character info can be brought into most the VTT's, things like conditions are not fully integrated. What ever condition modifications a given VTT use might work, but there's no guarantees that the bonuses and such will stack properly all the time - at least not as reliably as it does directly in hero lab.
This is the main reason I've been wishing for a long time for some sort of API that can activate abilities and such in hero lab, and pull updated stats from there - that way a VTT could be designed that let Hero Lab do all the math for it (leveraging Hero Lab's already rather complete game system rules). The few dev responses I have gotten from the requests have been pretty negative, so I don't hold out hope for it.