Once I learned that Mozilla was using Mullvad servers, my trust to Mullvad increased. Though, besides credibility I am not sure what other benefit Mozilla brings to the table by reselling it? Since they both use WireGuard protocol, client is mostly about UI, rather than functionality.

What would be cool, if Mozilla partnered with multiple VPN providers and had a multi-hop VPN with at least 3 nodes and multi layered encryption, similar to TOR.