Testing VPNs is a fun game and doesn't always end up with you bricking your internet connection each time you uninstall one to install another. Honestly. Not every time, anyway… We've sourced accounts for each of the services and tested them all on the same 100Mbit connection at the same time of day to ensure a fair reflection as to the performance of each of them.
There are free VPNs and some VPN services with free tiers, but you won't find them suitable for connecting while gaming online. They almost always introduce latency to your experience and severely hamper the overall performance of your network connection.
We haven't included any of the free options, such as Hola or TunnelBear, in this list. They're also not necessarily an effective choice if you're trying to get around geo-blocked services such as video streaming, as you may still find them restricted.
As for testing, first, I took a Speedtest.net measurement of my standard, unfettered internet connection, using that as a baseline against which to test each of the different services. Then I installed each VPN and tested it before uninstalling it to add a new VPN fresh.