What Material Is Best For Shock O rings?

Recently, I bought the Proline Ultra Reservoir Shocks, and like many other people, have had leakage problems. I narrowed the problem down to the material of the o rings: Silicone. From some basic research, I found that silicone o rings tear easily, and on top of that, are not even well suited for applications that use silicone oil. This made sense to me since I found severe tears in a lot of the o rings after taking the shocks apart (yes I did use a lot of green slime when I first assembled them).

So, what I plan on doing is to buy them from an aftermarket company made from a different material. So far, I have narrowed it down to three materials: Viton N75D or Buna-N 70D for most of the o rings, and Urethane 70D for the o ring inside the reservoir, since it has to survive a lot of abrasion. I would use Viton over Buna-N, since it is rated better for a compression-set situation, however I heard that Viton on 1:1 shocks tends to leak at lower temperatures.

Could someone who has more knowledge about this please tell me which material I should probably go with, and also correct me if I’m wrong about any of this? Also, even if the Viton material does leak on 1:1 shocks, could it still work on rc shocks without issues?
Thank you!

Also, I go into more detail about this on my build thread found here:

VRC 468x90 What Material Is Best For Shock O rings?

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