Why not openVPN?
I pay for PIA but use their openVPN servers.
Mainly because their windows client used to start a pair of Ruby interpreters that ran at 100% CPU and killed the battery life on my laptop.
Technically is there any reason to use their own propriety system rather than their openVPN service?
ps. I only need "stop my ISP marketing my browsing" level of security, I do my breaking into the Kremlin from work