Upgrade Thiel 7 s to 7.2 s ?

I have a second hand pair of CS7.2s that I purchased for ~7k that are in very good condition. I haven't heard the CS7s in comparison, so I can't comment on the merit of upgrading to the CS7.2s. In TAS's review of the CS7.2, one of the reviewers upgrades their CS7 to a CS7.2. You can purchase the review online for 3$ at TAS's website.

the 7.2's retail for 13K new . . .

the 7's are running in the 3K range used. The speakers are being driven by a Levinson 336, transparent cables. Supposedly the upgrade replaces all of the drivers with drivers that Thiel now produces in-house. It also reworks the crossovers. Has anyone done this ??

I performed the upgrade from Thiel 7 to 7.2 myself. It took two of us about 4 hours to change out all of the drivers, crossovers and input connectors. The only thing remaining from the 7 is the cabinet and some of the internal wiring. Without being able to compare them side-by-side, and after a long break-in, I would have to say the 7.2 is better in about every way. Sonically, it is more transparent, detailed and has more articulate bass. It is also a little more efficient and easier to drive, although amplifier matching is still very important (if the amp sounded good with the 7s, it will be great with the 7.2s). Is the change worth $4000? That's a little more difficult to answer. If you sell the 7s used and add $4000 to that, what speakers can you buy that you will like as well as the 7.2s? The answer for me was the upgrade - you'll have to decide for yourself.

I had the Theil 7's and also contemplated the upgrade. I then auditioned the Talon Khorus and never looked back at considering anything else. Much more musical and once broken in I've enjoy listening to music like I never did in 4 years with the CS 7's.