Andy wrote:

"There is no proof that the rings will harm chips, but I'm not taking the chance. I'll just use the direct fit air tites & leave the ring type to others."

Not a bad idea my friend! Synthetic plastics interactions can take years to realize, and by the time it happens, something has been damaged.

...without getting too technical, most hard stuff stays hard. Age makes it brittle, but that's about it. Most soft stuff changes, sometimes in a manner that is too quick for it to be involved in this hobby. It shrinks, it interacts with other plastics via heat transfers, and it does suck real color pigments from one surface to another.

...any foam plastic material will deteriorate over time. While the chemists are making progress in changing the formulas to make longer-lasting foam materials, materials that don't start sticking to everything that they come into contact as they begin to decompose, we won't really know if they have figured out that formula for many years, if ever.

Bob