Which guide to use for enabling Airvpn in a specific torrent client (and nothing else)?

[platzy398 0]

I just bought a small form factor mini-pc to use for torrenting and a local Plex server. I am looking to have it running 24x7 for Plex, and also for torrenting with Airvpn. I imagine I can use Ubuntu or Windows on it.

I would like to configure a torrent client to use Airvpn with a killswitch. I see some guides for various OS and variants in the how-to section here such as:
 

• The Guide for Torrenting, split-tunneling, killswitch and all the other buzzwords
• Prevent leaks with Ubuntu Linux & gufw/ufw (thanks to worric)
• Prevent Leaks with Linux & Firestarter (also Stop traffic when VPN Drops)
• Traffic Splitting: Guide to Setting Up VPN ONLY for Torrenting on Windows (thanks to NaDre)

And others. I am wondering if anyone can provide some guidance on which of the above methods might be best to use to prevent leaks? Would Windows or Ubuntu be preferred? 

Also my thoughts for having the torrent client only using VPN are to allow the Plex server to run without needing to go through the VPN, if that makes any sense. 

[OpenSourcerer 1441]

You don't need to go overboard with torrent clients. If you can bind it to a specific interface like qBittorrent, leak prevention is not necessary. As long as the designated interface exists, qB will transfer things using it. If it fails, so do all qB connections. For this I've found Linux to be easier – the tunnel will be called tun0, end of story.

You can simply operate Plex alongside the VPN connection. Access from the local network will work as usual.