1. How fast would you say rubber degrades when it is not being used?

I tried Tenergy 80 on both wings. Loved it on bh but not fh so am deciding between waiting for my current bh to run out before replacing it (which will be a while) or putting it on another set up for someone else to play with. 

2. What are some effective ways to preserve blades that aren't being used?  I recall reading somewhere that keeping Silica gel packets inside the blade's case/box is a good way to preserve its integrity by keeping moisture away.

For added context, I am currently based in a humid tropical country where it is warm to hot all year. The only seasons are wet and dry.

Thank you