Help: Thiel CS6 vs CS 2.3

NO waste on the McCormmack...but there are better amps. The McCormmack is a descent amp, which won't make for poor sound. I would consider others if you had the $. Even a used Pass X150 or 250 is much better. Heck, even used Threshold T200 is better.
I've sold/used both of these models in the past. Overall, the speakers are close. The CS6 is a better overall music speaker in certain ways. Not by a lot however. However, the CS2.3 is a better more effective HT speaker in my oppinion!!!! The reason? I find the 2.3 isn't as laid back sounding in teh pressence reigion as the CS6's!..making the 2.3 possibly the best HT speaker Thiel had made to date if you ask me. I've extensive experience with even CS7.2's and 1.5's and SCS3s/MCS1's And as an HT/music speaker choice, noto considering the Newer Thiel stuff, I think the 2.3 is the best for this application...IMO

....(but other than a brief listen to them in a showroom during a business trip, I don't have access to them to put them through their paces.)...

Akaddict, may I make an assumption in that you are going to dealers and listening to speakers(systems), and making judgement on the speakers from THEIR SET UP'S!?! Since there are a lot of varriables, It's too difficult without auditioning the speakers in other systems/rooms, including your own, to tell what's what! You're going to need to try em in your room, with your gear, after proper set up! That's the only way you'll ever know ANYTHING ABOUT THESE SPEAKERS PROPERLY AND FAIRLY!
I would suggest giving the pair you find a good deal on a try. And if you don't like em, then sell em and move on to the next pair! If you think you'll just buy a pair of speakers once as the "be-all" speaker to "end all" for your system, you may be fooling yourself! Because in the end, it's going to come down to trial and error, and experiementation.
I think when people try desparately to find gear that's "the best" for their purposes/situation, they'll find it's not a "done-in-one" kind of an endevor! You could get lucky...but if you really want to nail things down better, you gotta experiement..simple as that.
Why not try a pair of "something" you have a desire to try, and see what you can do with It? That's part of the fun, for me any way. I guess everyone's different.
As for my experience with the Thiels, I've always found MOST of the Thiel designs to be a little laid back and less involving for movie soundtracks than others. I do think the CS2.3's are the best of the older series Thiels for this application, but you need a strong strong amp to handle the HT! I've no experience with the newer Thiels for HT, so I can't commment. Although the higher sensitivity of the Thiel 1.6's makes for a good advantage for dyanamics. They might be a good chioce in a smaller/medium sized room/set up, or in places where you have "higher ceilings"....or you have extensive ceiling treatment.