I'm a representative of Quedex, let me clarify a few things:
- We don't accept US customers.
- We have a requirement to complete basic KYC during onboarding.
- We are constantly working on improving liquidity and UI - we welcome any specific feedback you may have. The liquidity is already pretty decent - you can most of the time execute thousands of contracts within ~20bps spread and it will improve significantly soon.
- We've been just awarded a Gibraltar licence: https://cointelegraph.com/news/gibraltar-grants-first-crypto-derivatives-license-to-local-exchange, and strive to provide a transparent and orderly place to trade crypto derivatives - as this milestone has been completed, we are planning to continue improving liquidity and expanding operations.
I am not so sure of this Quedex. I took a look at it and found that liquidity was practically non-existent. The latest transactions can be from a few hours ago. And I do not know if my eyes are too sensitive or what their trading interface is a pain in the ass.
Disclaimer: I have been trading on BitMEX for a year.