It's a 1SS and a 2SS that are different. RS is just an appearance package...
Main differences between a 1SS and a 2SS are leather, door and dash trim, ambient lighting, boston acoustics sound system, 4 pack guages, PDIM, etc.
Before everyone tells you to
I'll simply tell you the best way to learn all of the differences would be to go to www.chevrolet.com/allnewcamaro
and use the configurator.