mono block or bi-amps which would you pick?

There is no rule and no single answer to your question. It is all system dependent.  I run one system with 4 mono amps, biamping each speaker, and I run another with a stereo tube amp on it's own. 

I'd rather have a good sounding stereo amp than a pair of not as good sounding mono amps.

Wsphon... i totally agree with your point!  

Just want to say thanks for all the inputs from Audiogon members.  
 
I want to keep you all posted.  I decided to buy the Zanden 9500 mono block, 845 triode output/push & pull design.   The amp gets around 50watts pure class A.  To mate with that i bought a Zanden 3000 tube preamp.    I will see how it goes.   Happy Listening! 

Great move, zipost, let us know how it turns out.
Bob

Zipost, I've been tossing around the idea of the Zandens for a while now. 
Curious to hear how your system comes out, particularly the bass. The Zandens have the rep of being very smooth.