I see Nord and Proton as the best (don't know enough to really know more) but I'm leaning towards Proton for longevity.
I'm not going to mention which VPNs I have previously or am currently using.
NordVPN gets some very mixed reviews. Do a quick reddit search to see what I mean. Many people who have used it for 5 years and say they've never had a single problem, but many others who have said they cancelled their subscription because the speeds were so awful and their connection was frequently dropped. ProtonVPN generally seems to have better reviews, and also is recommended by
https://www.privacytools.io/providers/vpn/. Loyce did point out some concerns he had with Proton's Terms and Conditions earlier in this thread (
https://bitcointalk.org/index.php?topic=5203656.msg53206456#msg53206456). You can see my response afterwards and decide for yourself if it concerns you.
There is not much to separate them (as far as I can see) otherwise. Both are based outside 5-eyes countries, both have a good no-logging policy, both accept bitcoin, both have AES-256, etc. They do both offer a 30 day money back period, so there's not a huge risk to trying one out and seeing if it works for you, other than you might have missed the deal on the other one by the time you want to switch.