Our thomasnet program has been absolutely huge for us. We get at least a few calls everyday, and that translates into a tremendous amount of revenue. I would recommend any distributor or custom manufacturer to seriously consider a program with them if you are looking for ways to expand your reach.
Before thomas we were relying almost solely on google adwords, and not seeing the results we wanted. We were spending boatloads (think 5 figures a MONTH), and the adwords program just wasn't profitable for us. The calls we got were for really small orders. It wasn't adding up.
With thomasnet we get about a dozen RFQs and calls a week, and the orders are much much bigger. We developed ongoing relationships with many of them that have lasted until this day.
I read some of the reviews here and they mostly seem bogus. Misspellings, bad grammar, seems fishy to me. I wouldn't trust a reviewer who can't even type proper english.
Reason of review: On time delivery.