I have owned the Thiel CS3.6's for the past 8 years, and I am very pleased with them. If you are contemplating getting a pair, I would make the following suggestions:
1) The 3.6 has been criticized in some quarters as being a "bright" speaker. I don't think this is so --- I think that it is an "accurate" speaker. I reproduces what it is fed. You may find that, once installed, it becomes the strongest link in your system, which means that it becomes necessary for you to use associated components of sufficient quality. With the 3.6, poor source material and inadequate electronics have nowhere to hide, but if the 3.6 is matched with appropriate electronics, a good recording will sound wonderful.
My system includes the following items:
CD transport: Denon DCD-1650AR
Interconnect: Harmonic Technology Magic Digital One, 1.5m, RCA
DAC: Dodson Audio DA-217MkIID
Interconnect: Harmonic Technology Magic Link One, 1m, XLR
Preamp: Bryston BP-20
Interconnect: Harmonic Technology Magic Link One, 1m, XLR
Power Amp: Aragon 8008BB
Speaker Cable: Analysis Plus Oval 9, 8 ft.
Speakers: Thiel CS3.6
AC Conditioning: ExactPower 2000
Power Cords: Stock
Equipment Rack: Atlantis Reference 5
I upgraded my system in stages after I got the 3.6's, and each change was audible. The most noticeable improvement was the Dodson DAC -- this represented a huge leap from the stock Denon player, which makes a very nice transport. I still want to upgrade my power cords and add a balanced power transformer for the AC, as finances permit, but the system is coming together. The main point is that if you buy speakers that are good enough, then they will not become obsolete; they will reward you with improved sound each time you upgrade one of your system components. The 3.6's, in my opinion, are that good, and are one of the best audio purchases I ever made.
2) The 3.6 needs room to breathe, which means a listening room of adequate size. My living room is 14 feet wide by 19 feet long; the speakers are on the short wall, firing down the length of the room. There are 4.5 feet between the rear wall and the speakers' front baffles. Distance to the right wall is 2 ft. 8 in., while distance to the left wall is 3 ft. 8 in., with a 1-foot-deep bookcase taking up part of that. The speakers are 7 ft. 8 in. apart, center-to-center, and the listening position is 11 feet from the speakers' front baffles. I have them facing almost straight ahead, toed in just a few degrees to compensate for the less-than-ideal distance to the side walls.
I would have preferred a bigger room, but this is what was available. All the same, the system sounds wonderful with the right material. On some recordings, the stereo image extends beyond the speakers, and on most recordings the system has a good illusion of front-to-back depth. The 3.6's are 3 dB down at 27 Hz, and they produce excellent bass in my room. I listen to classical music exclusively (instrumental, chamber, and orchestral); bass drum, organ, and string basses have real impact. Solo piano has the requisite solidity, and orchestral recordings have satisfying weight and heft.
The 3.6 can be found on AudiogoN for around $2K. Compared to today's speaker prices, I think this is a remarkable value. The associated components that I have can be found on AudiogoN for a total of around $10K or so, give or take $1K - $2K. If your room is big enough, and you can see your way clear to acquiring appropriate electronics, either now or later, I encourage you to consider the 3.6's.
Good luck!
