I haven't but it makes me wonder if "superior" is just another name for "super" based upon the look of it ...
Even a super is "either 4 or 8 way"... what makes the t-stick and j-sticks unique (or rather more interesting) is that they are switchable nearly on the fly --> rotating restrictor plate. whereas, Happs supers "switch" between 4 and 8 way by taking the whole stick apart and flipping the actuator so that it has a narrower profile in order to not hit diagonals, which is NOT the same feel/result.
I'd be glad to hear that a j-stick-esque stick was manufcatured and sold by betson... but i'm skeptical, and hope someone proves my assumptions/concerns wrong...
*shrug*
rampy
look at this pic

Kinda looks similiar to your diagram from the betson catalog... which doesn't prove anything but means it's hard to tell if a joystick is good from a drawing =P