There is no best free hosting.

Mate, if you are searching for reliable web hosting, I would suggest you do not go with free web hosting or unlimited plans as there no guarantee about the site uptime. Earlier I also used free web hosting services, but due to the server downtime I switched to the paid hosting service. So I do not think so there is any best free web hosting.

Best free hosting is an incredible thing.

I absolutely agree with guys that best FREE hosting is impossible, because you'll always have as much as possible problems with free hosting.
As a matter of fact I'd like to direct your attention to Hqhost.net and site5.net, because, for example, Hqhost.net launched into Internet services market in 2001. That's why they are reliable and flexible ones. Thier prices are the cheast and support teams are the most attentive to the clients.
So, you have 2 choices:
1) to have problems all the time with free hosting;
2) to sit in a comfortable recliner and get rid of a stress.
It's up to you to decide.