Actually don't use a VPN. A VPN does not protect your anonymity, even if they pinky pinky promise not to log, you still have to trust that node.

Just use Tor + HTTPS everywhere properly.

It depends on the type of privacy you need. If you are torrenting or posting to a forum anonymously, using a VPN provider is fine.

If you don't trust any VPN provider, you can host your own VPN, or you can run a second VPN inside of virtual machine.

By what authority do you judge a VPN fine for torrenting (I assume you mean warez) or posting a forum anonymously (I assume you mean posting content that won't get you in trouble with your government)?

It entirely depends on your threat model, and who you are trying to be anonymous from. You could argue that using a VPN gives you relative anonymity for certain things, but that's a moving target. For warez, you might be safe, but using a VPN for something that gets more heat... well that gets you in hot water, even with a provider you suggest. [0]

Also, hosting your own VPN doesn't make you any more anonymous. Nor does putting that vpn inside a virtual machine. And I would specifically advise against it. Getting a warrant on your VPS provider account is as difficult as your ISP.

[0]: http://blog.hidemyass.com/2011/09/23/lulzsec-fiasco/

It can be a lot simpler than that, depending on where you live. I have a wireless connection for my home laptop, for which I never had to give my name when I bought it, top up in cash, never use my name in emails on that connection, and use Startpage instead of Google. Total anonymity.