Gas/oil additives

Does anyone have any experience with gas additive Ethos or gas,oil and transmission additive Motor Silk?

Ethos is a scam. It is feeding off the fear of high fuel prices.

I have heard mixed reviews about Motor Silk. I would guess it is OK, but you would likely be better off just changing the fluid and cleaning the filter.

The fact is modern oils, lubes and fuels come with all the additives any normal car needs.