I don't trust them, but based on some assumptions. They are statically less likely to be taken down. That cannot be argued, but because of strictly enforced rules, most (at least the ones I've seen) do not allow VPN IP addresses to be registered. The issue there is the user has a forced increase in reliance on the site operator to maintain pseudo-anonymity.

The fact you were able to buy in without any proof of who you are or that I've encountered people just giving away invites to strangers, would suggest at least some of these trackers are not trustworthy. What protects those communities is their insular nature. Once that's circumvented, its essentially just the same as a public tracker.