It is better...I have the 60.7cs...they sound nice...You can run it at 2 ohms, which means that you can power 2 pairs sufficiently with a single 4 channel amp (no bridging necessary)...it is also 4-5 db more sensitive so if it were the same sensitivity as the 6.1's, it would handle more power...even on the internet, others give the 60.7cs better ratings so far than the 6.1 has received...not only that, but the 60.7cs is cheaper too...can't go wrong man.
ive heard 6.1's and have the 60.7cs...the only real difference that can be considered a positive or negative for anybody is the new 2 ohm impedance. With 2 ohms, the amp sees more THD (total harmonic distortion). about .03% more...which is not noticeable. the coaxials used to be the same type as the 6.1 but have been changed over to the .7 series...i don't know...to my ears, the 60.7cs sounded faster.
I can't wait till they come out with KAPPA AMPS...its long overdue. Their reference series is so old and out dated...12 db/oct crossover? are you kidding?