Ribbon, planar and AMT tweeters all measure worse than good dome tweeters of similar cost. They invariably have narrower dispersion due to their large size - sometimes much larger size - and have far greater distortion in the 2-4 kHz range which is where tweeter performance really matters.
The RAAL tweeters are generally the exception to the rule and many people regard them as the best tweeters available, but their narrow vertical and comparatively narrow horizontal dispersion is something that has to be accounted for. The bigger AMTs can be pretty good too.
However, if you're looking for state of the art distortion and dispersion, modern hard dome (corundum, beryllium, aluminum) tweeters are generally where it's at, especially if they are loaded in shallow wave guides.
Having said all that, people do like the way ribbons and AMTs sound, and consumers seem to like buying them. Some of the really expensive RAALs have super low distortion, and their frequency response is incredibly linear.
You can see some measurements here if interested:
https://hificompass.com/en/reviews/bliesma-t34b-4-beryllium-dome-tweeter high end large dome tweeter
https://hificompass.com/en/speakers/measurements/raal/raal-70-20xr medium sized RAAL
https://hificompass.com/en/speakers/measurements/dayton-audio/dayton-audio-amtpro-4 large AMT
https://hificompass.com/en/speakers/measurements/sbacoustics/sb-acoustics-sb26adc-c000-4 inexpensive aluminum dome tweeter - I suspect a variant of this is used in the Revel speakers you're looking at? The new version of this tweeter is ceramic coated and I suspect the breakup is pushed even higher now.
https://hificompass.com/en/speakers/measurements/peerless/peerless-da25bg08-06 very inexpensive (seen them for $15) aluminum dome
See below graphs. Tweeter performance is a bit like DACs in the sense that for very little money you can approach state of the art performance if conventional, optimized technology is being used. If you feel there is some magic in an alternate approach, you can spend a lot more money to get slightly worse overall performance which may be optimized in one or two ways.
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