Free coins on Yobit is worth if you have much time for spending on these page. Sometimes there are coins that can be trade on free coin list, it's need regular refresh on the site.
Well, free coins actually doesn't need a lot effort, so the value is just a penny or even on the list is not worth to trade anymore.
i think it still not worth if you have more time to spending on these pages because you just earn less than a dollar on free coins in a day.
so i think it will be good if you spend your time to other bounties than claiming free coins.