Thomas,
I purchased a Super Belt (clear/white) with my 2800 about 2.5 years ago. I never compared the Super Belt to the belt that comes standard with the 2800.
About a year ago, Basis came out with 2 new belts. One is called the Revolution Belt (black). The other belt is part of the Basis Synchro-Wave upgrade. I purchased the Revolution Belt.
I think the Revolution Belt is an upgrade to the Super Belt. Based on measurements with my KAB strobe, I can see that there is no oscillation of the stationary point with the Revolution Belt. It is rock steady. Talking to AJ, this can be attributed to the in house manufacturing he is doing with the Revolution Belt allowing him to better control the belts thickness along its length.
I dont know if I can pinpoint a sonic upgrade with the Revolution Belt as my 2800 with Super Belt (Vector MK3, Lyra Titan I, Aesthetix Io, Walker motor controller) already sounds excellent.
Rich