For whatever it's worth, I have had really good performance from the silicone Kabuki rings. I have 5+ Kabooks in a mixture of P3 and 510 flavors and the silicone rings have worked perfect in both. The same can't be said from previous o-rings. Some worked well for one, not so much for the other. If you are running both I highly suggest the silicone. If not, there are rings that fit one better than the other. PM me if you want specifics.