I've used Displet's IDX system for 2 years after they built a custom site for me. In short, it's awesome. They advised me to build out a number of niche landing pages and to drive traffic to those pages, which I did. I started out posting craigslist ads and got busy enough with leads that it made more sense to pay for traffic using Google Adwords. The niche pages convert extremely well. My website loads quickly, my customers like it, and I sell houses because of it. Other than referrals, it's my #1 source for business.