Yeah this is definately not chump change. So really it's a hard thing to just "try" without any solid reviews. The big thing is getting these profile links indexed, ok you got 70k links, Great. But what really matters is how many of those will get indexed.
One thing that really cautions me, is his other service offering, the 1-2 people that left reviews. Stated that half of his blogs were on the same domains. Which really makes me think twice, if we are going for overall SEO. You at least with that service, you want unique urls on different C classes and of course different properties/domains.