Scoring on Used Thiels here

http://www.psaudio.com/bhk-signature-250-amplifier/

Unsound ... you are right the Thiel equalizer has a high input impedance ... either the 90k you mention or perhaps 100k.  That is why it can take the high output impedance of the SP6's or other pure tube preamps.  However, its output impedance is very low, so it works well into the 10K input impedance of the Outlaw monoblocks, which is low even for solid state amplifiers.

There are a pr of Thiel 2’s on local Craigslist , look good , wants 250$, is that a good deal ?

Been looking but may have to wait to play with something new  in that some unexpected household repairs came up.  

Problem is WAF will be a problem with 2-3 models large enough to possibly eliminate need for a sub.    1.6 woud work but be more of a lateral move so no huge incentive there. SCS monitors would fit nicely but have not come across those still very much. 

Also still not ruling out various  other lines still as well but not likely to do anything for a while now.   What I have sounds very good but I do like to try different things.  

The info on this thread has been very helpful so thanks  to all for that.