The company behind the technology (fullpower) maintains a full sleep lab to constantly test the sleeptracker's performance against polysomnograph results. They claim better than 90% accuracy on the SleepTracker's ability to distinguish between the different stages of sleep.
Anyways, I was searching their site for something else, and noticed this link. Wanted to get it out there for anyone in the area, or within a couple of hours. It's a great opportunity. I'm kicking around the idea of signing up my wife(never has had a sleep study) and myself, and planning a vacation around it. We enjoy San Francisco - plenty of things to do in an around this area.

https://www.fullpower.com/studies/sleep