Gunbei - I auditioned in my home the Tablette Sig. before deciding on the 2.5s 7 years ago as I really hoped to find something less expensive. The Tabs were so bright and, as my wife called them, cold sounding that I couldn't even consider them. This with a triode P/P amp.
I then tried the Response 2s in my house and it was beautiful sounding but a bit too beautiful, if you know what I mean. Wonderful late night classical music speakers, though. I finally did spend a 2 1/2 hour private listening session with the 2.5s at the dealer using an 845 SET and an 25 wt SS and fell in love. Bought them that day and have not looked back. In fact, just this past week I treied to sell them to see if I could find something better and more musical, got an offer (on the low side) and decided to withdraw from the market. I just can't let them go! I actually thoroughly enjoy just looking at them and it made me quite sad to see them sitting unplugged my the family room. Last night I dragged them back to listening room and decided in 2 minutes that I'm going to keep them. Besides, this makes my wife very happy as she actually paid for them with her bonus that quarter - and we all know how our wonderful ladies get sentimentally attached to things! (I guess me too.)
I also listened to 1sc with SET amp (Cary 300B which is a bit on the warm, dark side of things) and found the ProAcs etched and uninvolving. But remember, just like we all taste differently, we also listen differently.