I have been using this for months and really like it. But I will warn people how easy it well it works depends heavily on the provider and protocol you use.

I have some experiences below, but I would just ask the creator of Gluetun what they use because it will be the best documented and supported.

Cyberghost worked well with OpenVPN but they do not allow port forwarding so I switched to PureVPN. PureVPN was awful, they allow port forwarding but you have to use very specific servers and there's no way to control that with Open VPN on Gluetun because the server list is not up to date. I tried Wireguard and it worked but the slightest connection drop would cause port forwarding to stop working and I would have to redo the connection with new keys and all every time. Eventually it just stopped working no matter what I did and support was kind enough to refund me. I asked for the remainder of my subscription and not only did they not try to argue they gave me a full refund so that's points for PureVPN.

Right now I'm using AirVPN which works really well. Once in a while port forwarding will stop working. But if I switch to another port it works again, so I just keep two ports open and change things client side and that seems to be the path of least resistance.

Another nice feature of Gluetun is an http proxy you can enable. Handy for private trackers that only let you access it from one IP for downloading and browsing. Just use an automatic proxy switcher in your browser.

Edit: fixed that last bit that was typed off screen on my phone because the kbin mobile site was being funky.