I have done 2 studies with them in the last few months, and both have been great experiences! I did the fever study, and the insomnia study. The fever study was kind of rough because they have to make you sick. I had a fever, and had really bad chills. It was still worth it though. I only felt bad for a couple of hours, and made $900 for being there for 2 days!
Their studies are sort of few and far between, but they are getting ready to do the 2nd part of an insomnia study. It's $1200 for 4 days, and you don't have to have insomnia. I took part in the first part of it, and it was a good study. I didn't have any side affects at all.