Mullvad, using it since age, never failed me, speed is as fast as without it. Mullvad is usually a top pick among the privacy paranoids. Strong and secure VPN.
The server did not contain user activity logs, but the hacker stole a Transport Layer Security key, which temporarily opened the door for a 'man in the middle' attack. The hackers may have also gained root access to the server, enabling them to potentially view and modify VPN traffic.
A VPN service copied our extension's design, they use(d) our API servers and implemented their browser proxy service insecurely. We make this incident public to avoid the awkward moment when someone might accuse us of copying them and not the other way around