Well,

I haven't used any free VPNs and honestly not sure how well they will work (low ball speeds and such). But thinking about Netflix, the speed is the first factor that comes to my mind as you'd need to steam faster. I've used Netflix with PureVPN and I can certainly recommend it. It's dirt cheap as well. In fact I did a review for it including a video review where I do speed tests, you can see for yourself if you want here - http://www.thebestvpnguide.com/purevpn-review/

If you need any help, feel free to ask.