I used them for a while. It seems to be a pretty good system if you work it right. You can choose zip codes and what work you want to bid in each one. It does a pretty good job of bringing in the work.
A couple of problems that I had:
Small jobs. I wouldn't mess with them. You have to go look at them then price against 2 other company's. It didn't seem to be worth it unless you can price them over the phone.
They send you contact info for people, phone, email, etc. Some people I could not get a hold of. I don't have time to call and call and call. I was charged anyway. There seemed to be several like this.
It seemed to work better for larger jobs, generators, remodels, additions. I think the rate was about $50/lead.
You get the opportunity, but its up to you to make the sale.
My word of mouth business picked up so I stopped.