NI's B4 II has MIDI problems. Notes stick even when it is played by itself. Everything else works; it sounds good; it just doesn't respond well to the MIDI.
GSI's B3 VST works fine.
The Inexpensive SONIVOX VIs are working.
Even though BFD2 is reported as tested and working, I've had problems with it sometimes not reloading. Most of the kit will reload, but one instrument such as the snare will have to be manually reloaded. This doesn't always happen. I don't think this is a VE Pro issue as I've seen similar behavior with the combination of BFD2, FX Teleport, and jbridge.
I can also confirm as stated above that Real Guitar and Real Strat work with no issues.
I'm using Cubase 5.1 on a 64bit Vista machine talking to two 64bit Vista slaves.