I've home exchanged with my family throughout my married life. We've never had a bad experience. Each year we plan one major vacation in a foreign country for 2 - 3 weeks, and in addition we do several mini exchanges, much closer to home. Our two children have benefited enormously - instead of run of the mill packed trips they've traveled the world, truly "lived with" the natives, and, I believe, are far better people for it. They are more tolerant and understanding of their fellow man. Less prone to misjudge and condemn people from other parts of the world out of hand, after all, they've lived with them.
We've always used one company - exchangehomes.com to arrange our exchanges. They've been around for years and have always provided excellent customer service. We've looked at others, but most of them seem to mix a lot of vacation rentals in with their exchanges and then it becomes hard work and difficult sorting out the listings we're really interested in.
With home exchange I truly believe that they key to getting it right lies in allowing plenty of time and making sure you discuss absolutely everything with your probable partners. We have agreed to disagree in the early stages more than once and moved on to look elsewhere.
Discuss everything down to the smallest detail and then put everything in writing. ExchangeHomes has excellent sample agreements. It's worked for us for 26 years.