Y'all I have to say after having almost all Mike's cabs I have really settled on the MAS 66 with a 110 Sub on the bottom.
It is so right in the midrange and driver integration plus it gives some of the slam of the 210 flex.
You Nailed the crossover on the 66 man! It sounds like a giant hifi rig!
Wow. If the mid-range presentation is a cut above that of the Flex series, that's saying something!