

Since it’s free, huge number of people are using those servers. You will get a lot of captchas and many sites outright block all those IPs.
Trustworthy? I am okay with them, but if I need something more private I’d use Tor.
If you’re considering spending any money with them, I’d say go with Mullvad, since it would be cheaper. If you want all Proton’s services bundled, they can be good.
I really want to try this, now.