They're a step up from Proton in that they haven't been known to provide user data, even know Proton never really gave user data, only a users recovery email and suggests you don't use one if you're a whistleblower etc. Mullvad is nice cuz you pay for it with gift cards, even some physical stores sell them,which is pretty anon. You can pay proton in cash through the mail, which is also pretty cool. It's a toss-up between them two but what wins for me is Proton being in Switzerland, that alone is fortification.