[Dezoris]

The SS do not have helper srpings. The main use pillow mounts is to stiffen the mount up top, which results in higher feed back, and increased spring rates (Slightly)

When you use these it is recommended that helper springs be installed, to reduce the vibration and initial shock that is produced from the mounts. Hence the term "helper" they do the initial load balancing then the main springs do the rest.

So since the SS do not have helper springs the pillow mounts are NOT recommended.
They go hand and hand.