I don't want to start World War 3 here. The bass in the Exotica is simply more accurate than the SS8's. The Raal tweeter is very , very good. It may well be more "accurate" than the soft dome in the Exotica. Maybe the soft dome in the Exotica is "colored". The things I value most in a speaker are clarity, dynamics(it must sound "alive") and a naturalness to the sound especially in the midrange and vocals.
Of course, the Exotica already has super clarity and is very dynamic. I think Jim made a great choice in the mid woofer and tweeter. The mid-range and vocals just sound more natural to me than the Raal tweeter. The Raal tweeter may very well have more clarity than the soft dome tweeter. But what gets you excited in this hobby is the emotion connectedness you have to the sound. Jim has an outstanding job of provided clarity, dynamics, great bass,(they rock!), and a naturalness to vocals and the midrange that is better than any speaker in he made before(IMHO)