Is there any description available about how that OBFS4 tech precisely works? Is that some anon tech that XSPEC uses specifically or are there other coins using that, too? And on your OP you say it's anonymous almost anywhere in the world so I assume it depends you can use it anonymously wherever TOR offers exit nodes or what's the limitation to fully global anonymity, if any?
To understand OBSF4 in general, go to the Tor website :
https://www.torproject.org/docs/pluggable-transports.html.enAFAIK, only XSPEC has OBSF4 fully integrated.
XSPEC is "built" on TOR to anonymize the communication between nodes. Some countries (China in particular), however, is blocking TOR. To shield from such blocking attempts and make appear TOR communication as any other internet traffic, OBSF4 is used by TOR itself. XSPEC's technology leverages TOR and OBSF4 in its core.
It is thus the only coin that has inherently the same level of anonymity as TOR communications in general, but cannot be blocked. (Actually, one small but important point is that since TOR is integral to XSPEC and XSPEC transactions never leave the TOR network, XSPEC cannot be attacked at the TOR exit nodes, like other coins which simply use TOR for transportation)
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