I've owned the Thiel 2.3's in the past. And I'd own them again, sure. They do need a very strong, high current amp to make em come alive dynamically. They also do well with an active preamp. I think solid state high current amps work well with them, but you need some tubes in the preamp. I think this combo is best and most practical for a wide varriety of source material. If you do HT, it's a no brainer mostly(I take it back, if you set em as "small" for HT, you could do tube amp). Infact, for HT, I've found no better Thiel than these! They have good pressence, and aren't so laid back sounding throughout the "pressence region". I've tried all the Thiles for HT, and the 2.3's just seem to do it better...my experiences anyway.
If the deal was right, I'd recommend picking em up and giving em a try! I think you'll not likely be dissapointed with proper matching gear and set up. They're nice speakers...just not perfect...like every other speaker...but still refined, clear, detailed, open, and pretty dynamic with the right amp!
good luck