Has anyone heard the new Vandersteen Quatro?

Around $6K is what I recall.

I heard $6,500 but you have to assume you are going to want model 5xovers unless you want to build your own. If you want model 5 xovers, I think they are about $800 balanced or $600 for rca. Making your own could be much cheaper and may provide satisfactory results. If you are interested, I would do a search on this forum as I believe it has been discussed in the past. Most people do not advise using the "regular" Vandersteen xover.

Does anyone know what drivers it uses?

See this associated thread.

http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1073928086&openusid&zzZargon&4&5#Zargon

Hi,
The Quatro's should retail for $6,500/pr. They use the Model 3A Signature tweeter and midrange drivers with a new 6.5 inch mid/woofer (rather than the 3A's 8 inch). The bass is handled by two 8 inch woofers powered by a 300w built in amp. They should become available in the June/July timeframe. More information on the bass controls and subwoofer crossover will be forthcoming at that time. I suggest contacting your local dealer to stay up to date on Richards progress on shipping them.