I owned a pair of Thiel CS.5 for a while and also heard the 2.3's (they were not quite broken in yet). I have not heard Vandersteen. I will say that the theil was a nice speaker for the year and a half I had them and hated to see them go because they are a status speaker of sorts. If the Vandy's are where your heart is heading go with'em, If you've owned one pair of speakers for 25 years you don't seem to picky like alot of us. In complete opinion free from the speakers you listed above I think the Biro L/1's by avahifi.com would provide more musical sound and you would save money and space. And with the money you save you might even want to upgrade something else. The L/1 is a very special speaker.
VANDERSTEENS vs. THIELS
Dear audiophiles, I'm getting ready to buy some new speakers after 25 years of using AR10pi's. I've narrowed my choices to Vandersteen's 2Ce, Thiels 2.3, magneplanar 1.6. Please give me your thoughts on reliability, accuracy, other comments. I will power them with Onkyo m-504 amp (150w/ch) and use rega phono and cartridge,some CD's on a Denon 370. Thanking you in advance hififile, (aka: Bennett).