Viscosity is one of the absolute best VPN clients for Mac (and Windows). It’s very popular and I use it personally for a variety of reasons. I’ve put together a handy guide to help you get started with Viscosity.
Viscosity is not free, but it does come with a 30-day trial and then it’s just $14 for a license. Well worth it imo.
How to install and configure Viscosity to work with Ghost Path servers
Here’s the full list of Ghost Path VPN servers. You can click the Viscosity link for any of those servers to download a pre-config’d Viscosity file.