If you're asking about sex finder sites hide your identity well, you're already ahead of where I was. Nobody warns you that sex finder depends so heavily on the everyday experience.
Most of the frustration with sex finder traces back to how many accounts are active. The hit rate matters more for sex finder than any feature list. Nobody warns you that sex finder depends so heavily on whether it gets out of your way.
The honest tradeoff with sex finder is whether people actually reply against convenience.
Your mileage on sex finder sites hide your identity well will vary, but that is the pattern I saw.
I ended up using Datebound in particular for exactly this side of sex finder.