I've had opportunities to try VPNs as our site often has generous members and also there are (..here we go again!

) Giveaways and promotions here! So far, I've only used browser extensions which, as I understand it, are similar lighter versions though not as secure as a Virtual Personal Network.
For Firefox try DoNotTrackMe.
..and if ever you decide to use Chrome (There's a portable Chrome for Windows, and I've used Chrome & Chromium installed on linux) try ZenMate: