I'm sure it's great
i guess I never tried it because I figured it was better to separate browser and VPN
Discussion
Mullvad is = Librewolf, but your cache/cookies are deleted on every session. It acts just like the Tor Browser but without the Tor Network. You can achieve the exact same thing with Librewolf or Zen.
Forget about fingerprint, it's a battle you can't win.
Auto deleting cache / cookies results in horrible UX
I assume mull works like LW and you can toggle exceptions for sites you want to remember
Exceptions won't work on Mullvad, just like on Tor Browser. If you want exceptions, use Librewolf.
For the average user yes. My internet is fast and my password manager deals with my logins in a single click, it doesn't affect me.