I have Oil Eater. It's just OK. Biggest issue is you need to dry the part almost immediately after washing or it will flash rust. Also, the ratio they list is not effective. I needed to double it for it to even do anything.
It seems to work better when warm to hot, so a tank heater may need to come into the mix.
It's not like the old stuff that's for sure. I do not plan to buy it again.
This is stuff I have in my 30 gallon cleaner now.
https://www.amazon.com/OIL-EATER-DEG.../dp/B000EANNDM