Pociwo the PIA app used to be recommended but has since been removed, the issue surrounding the project itself recommending providers/apps etc is that the space changes so often, mergers, buyouts etc that you never know who you could be dealing with and placing trust in from one moment to the next.
Therefore the best position for the project is to remain provider agnostic and only recommend the generic protocol apps.
That said however from a personal perspective, I would advise you to do your own research and choose a provider that fits your needs. A good place to start would be somewhere like the Freedom of the Press Foundations article (recommendations at the bottom): https://freedom.press/training/choosing-a-vpn/
As mentioned check to see if any audits have been done, their transparency reports and if they have warrant canaries etc as par for the course.