Zip GS questions

[Ben Lai <benlai@unixg.ubc.ca>]

As a new IIgs owner, I am a little bit confused about the Zip
accelerator for the IIgs..

At EGO System, they are selling a "ZipGS 8/16 accelerator", what does
the 8 and the 16 stands for?  They claimed that the chips runs at 8 mhz,
so I assume the 8 stands for megahertz, and the 16 stands for cache
pershaps?

Yet, at Alltech they are selling 7mhz Zip Chips for a lot cheaper than
the ones by EGO System ($140 versus $175), what is the difference
between the two?  

Also, I remember reading something about Zip GSX, what are these?

Any help would be much appreciated.
 
Ben Lai