biamping my Virgos - can someone educate me?

The virgo's crossover is speciffically desgined not to use biamping. Not sure if this is going to help you. IMHO.

It shouldn't be to hard. The Virgo crossovers are parallel wired so you can add a pair of terminals that would be connected to the low pass filter for the woofers. It would need to be disconnected from the rest of the network. The bandpass and high pass would remain connected to the original terminals and that is what you would use with the S.E.T. amp. Gerhard Jochim (owner of Audio Physic) doesn't believe in bi-wiring/bi-amping so thats why he builds his speakers with only one set of terminals.
Bi-amping is probably not as good an idea as bi-wiring because the two different brands/types of power amps may not have the same amount of gain. If they are more than half a db off then you will get more treble or more bass then you should and the speakers might sound either too forward or too recessed in the midrange.
On the plus side, if you can get two amps (one solid state and one tube) with the same gain, then you can get the best of both worlds...great tight bass and the sweet mids and highs of tubes.
I think that you would be better off investing in a good powered sub to go with the Virgos to fill in the bottom. They kind of suck below about 50hz in my room and I really doubt that Bi-amping will fix that.