How do you view PBNs in 2017? Would you ever consider purchasing a site that is ranking with a PBN or is it just too risky? I've read conflicting opinions, so

How do you view PBNs in 2017? Would you ever consider purchasing a site that is ranking with a PBN or is it just too risky? I've read conflicting opinions, some saying that if it is done is a silo'd way and the content is not terrible, its not such a big deal.