Definitely no scam, popunder, blind, skimmed traffic gets delivered quicker but isn't targeted as well so usually good to boost trades, increase alexa, set cookies etc...
All of his traffic is clicked text links so slower delivery but has a higher chance of actual sales as more targeted. I have compiled a list of sources I buy from since 2002 that works for me and he is one that has never been removed from my list, nice guy as well.
Most of the sources I buy from since 2002 where I see a positive ROI all deliver slow and are targeted descriptive text links, have some places I advertise where I get even less like just a few hits a day but the ROI is there so small numbers with results can be better than high numbers of less quality traffic.
