The Bestchange link in OP contains a lot of scam accusations across many review pages indicating Quickex have confiscated money from users without returning them, which means they have scammed some of their users.

Quickex have also failed to provide any proof of them having a registered company in Seychelles up to this date. The company they expose on their website named Angel Ventures Limited with a registration number 238203 does not exist in Seychelles. There is my reply in their thread asking them to provide any proof of existence of their company, which they have failed to do: https://bitcointalk.org/index.php?topic=5503896.60

An exchanger that lies about existence of its company is not only performing a prosecutable criminal act, but also should be considered scam/fraud, given they "confiscate" (or simply steal) money from its users without having any legal right for doing so. Any existent AML/KYC regulations do not apply to anonymous entities like this exchanger, because without a properly implemented company they can't really comply with any AML/KYC regulations (a proof of this can be found here https://bitcointalk.org/index.php?topic=5509747).