Being a premium member has little to no benefit - except for supporting Michael. I've (and many other users) been asking to fix the cookie problem many times so we don't have to login to forums every times we want to read a new post to see ad-free article. Years later is still doesn't work as we would expect it.
At the end of the day I gave up. I decided to pay a premium member fee and use ad-block. This way I have ad-free experience out of the box (without clicking forums button followed by "back" button) and still support Phoronix.