Connecting domain with Github

I want to connect my website I have on Github Pages with my domain. The registrar I have bought the domain on, doesn't allow more than one A record on freedns - and Github says I should add four.

So they have asked me to create an account with http://freedns.afraid.org. I have added 4 of their nameservers to my registrar. I have also set all four A records from github on afraid.org like this

Now I have two problems:

1) The website sometimes loads fine, sometimes it appears offline and only loads after I refresh it like 20 times (few minutes pass). What could be the problem here?

2) The address with "www." doesnt load. I'm a bit of a newb still, should I add same IPs for all four A records with "www."?

And lastly, is this solution with afraid.org good one, or should I avoid it and but some other hosting alltogether / transfer domain to some registrar that offers 4 A records? I'm on budget because of multiple sites I want to create.

Thanks!