Did a search- advice on Royal Purple
 

Two friends who build transmissions and one friend who used it say that Royal Purple will make my T-56 quieter and much much smoother, less notchy.
But then I read on here not to use RP.

Royal Purple makes synchromesh and Regular that says it is Dextron III compatible.

From reading on here, two years ago Liberty Trans said they put a blocker ring in RP and then Mobil 1 ATF. The RP made the blocker ring deteriorate. Problem is, did they use regular or Synchromesh and does this only effect stock paper blocker rings or replacement carbon fiber blocker rings? Theres four different scenarios there. I trust my friends but some people on here I respect like Slowhawk say not to use RP.

Opinions/facts wanted....