I used a pair of Fried Beta Signature's for many years (along with the matching Fried "The Subwoofer") and agree with Shubert's finding although I would add that tube amps really made the Beta's come to life. EL34 based amps were especially killer.
In addition, a sub is really needed with the Beta's as used on their own, they are satisfactory but due to their
"Distributed Loading" of the mid/bass driver, there can be audible "noises" that are heard over the music when bass heavy material, especially high level bass kick drum, is played at elevated but clean levels. If your musical taste is mainly classical played at low to mid levels, I doubt one would ever be aware of the distributed loading issues.
High passing the Beta's at ~80hz/6db per octave as is done in "The Subwoofer" solved the noise issue and also increased the dynamic range of the Beta's which enabled them to really come to life.
I have not heard the other Fried models you mentioned but if you come across some used Beta's, especially the Signature series, grab them as you won't be disappointed!
Cheers
