I love them. I have a couple much less expensive DIY kits and PSB Image T45s. I built a switch so I could do A/B/C comparisons and gave it to my brother to do the switching. He did not know which speakers he was turning on so it was a pretty blind test. The highs and mids are much clearer than anything else I have. I don't consider them bright but others might. The biggest difference is in the detail or clarity. I didn't consider the PSBs muddy before comparing them to the Tanzanites.
Another observation has been how clear dialog is when using the Tanzanites without a center. I was used to using Dolby or DTS to matrix 2.0 audio (from video) to multi-channel to use the center. Now it is not necessary. I can't wait to build the Sardonyx center channel.
As for the sensitivity, I don't plan on doing any actual measurements but they seem to be around the PSB's which are rated at 90db anechoic and 93 in room. The trims are in the same ballpark but I find myself not needing to crank movies quite as loud because of the better clarity.
These are bookshelfs and the bass is what I expected. I have them a few feet off the walls and they put out nice sounding but not very powerful bass. I would take this bass over something boomy any day. I have no doubt that placed closer to the wall that these would be very good performers. I would test it by moving them but my room is a converted attic with a pitched ceiling and I can't do it. I have 2 subs to handle the bass and they blended nicely.
I'd love to take them to an audio store to compare them.