Visually, there are many differences. Summarizing:
Could someone list the differences..they are not readily apparent.
And which one is the more desirable...and why?
The Super Polaris (SP) has a greater payload than the Polaris.
The Polaris works extremely well in alt-az mode. The SP is not as well balanced in alt-az mode.
The SP is a lot heavier, is a marginal grab-n-go.
Both axes can be driven on the SP, only RA on Polaris.
I would think that tracking precision is the same for both.
The SP is a lot more expensive (both mounts are available only on the used market).
The SP has been cloned many times. There is only one Polaris.
Later SP clones have ball- and thrust-bearings on the RA axis for even greater payloads, the original SP and Polaris use plain bearings.
Desirability is a user-determined value. I have both (actually a CG5-clone) and use the Polaris far more often because of it's portability. YMMV.