Medlin04. I agree with Robert, it's a cost-reward trade-off.
Since it's the paving industry we're talking about, how many nice relevant sites can there be ?
I doubt there are very many that carry substantially higher PA/DA. Your customer's competition will face the same problem of available relevant links.
Unfortunately, G's continuing attack "freshness", Panda, and now Penguin will continue to favor the sites Robert dubbed "PA-60" sites which have high "authority" but are usually written by content writers who, no matter how good they are, often do not fully understand the subject however experienced and skilled the writer may be.
No matter how anyone characterizes it, G's culling websites. Saves on search, helps sell adwords. If there is a huge (intentional) weakness in G's formula, it's underweighting relevant small business links out to other sites in the same business. I believe this part of the algo is intentional because the big sites often sell the advertising which directs the traffic to these small business.