Originally Posted by thekctermite
I didn't insinuate that it is.
If it ain't broke don't fix it. Wax has worked great for decades.
I know you didn't.
But, taking a step back and thinking it over...as I said, the drain is not under sustained pressure so either wax or rubber should work fine. I have never heard of a rubber seal, but rubber seals are common in almost every water application and used in extreme pressures. I'm sure the manufacturer has good arguments on why it's better than wax.
With regard to the "it ain't broke" statement, if people/companies abided by that argument, you wouldn't have pvc pipe, shark bite fittings, pex tubing, spray foam insulation, etc. to replace the still good options such as copper tubing and fiberglass insulation.