Been using mullvad for at least 3 years, no major problems so far.
Currently I'm not using it so much and my subscription ended 2 months ago, so I'm using the free version of proton which is good enough for the basics of using public wifi.
I'd like to say that it's useless but after experiencing dropping a full latte on my thinkpad some time ago and the magic drain holes working properly and the laptop surviving afterwards makes me really appreciative of the feature.
When your school life ends and you realize you'll never have 3 months vacations ever again in your life and will only have rest again after 47 years, if you live that far...