Careful with thinking VPN automatically cuts ping. I once ran a VPN during a raid in a game and my ping shot up, not down. Sometimes it's about the route, not just the VPN.
Spot on. If you really wanna check if a VPN leaks or not, run a leak test on a site like ipleak.net after setting it up. It's quick, free, and shows if your IP, DNS, or WebRTC are exposed. Do that before trusting any VPN for sensitive stuff.