To speak frankly the Traffic factor is slowly diminishing from known Dofollow sources. And now you have to choose between a Dofollow link and relevant traffic. Most websites that bring in traffic are no longer offering a Dofollow link.
The same applies to Social bookmarking sites, Reddit for instance is one of the best source to get traffic online, but yet it is no longer treated as an SEO site. To me Traffic is more important than a simple link, a link that can bring in traffic and relevance is more important than a mere do follow boost. In reality dofollow and no follow are not that miles apart from each other. In terms of SEO Google uses both these links to decide the value of a website, PR was the only reason why follow links are still hunted. But PR itself is dead, now and Google has reduced the effect it had on SERP ranking.