I'm one of those that had positive ranking effect with n-o-f-llow links from comments. I've noticed lately that n-o-f-ollow links from SB blast had no positive effect and might even had a negative effect but I'm not sure about the negative.
On the other hand, with profile links + indexing them, I saw a positive impact on ranking but less than it used to be.
My understanding is that Google de-valued significantly (might be totally) the n-o-f-ollow links for ranking.
In addition, I think Google devalued the link juice from pages that they identify as poor value.
Profile pages are mostly considered duplicate pages on the same sites and therefore I think eventually will lose their effect.