I am using usertesting.com and contributing them for the past 1 year. Initially when I registered with them they sent me good amount of work. Their service was good at that time. But after some months they stopped sending me work. I have contacted the support team and they kept me wait. The payment process is also so poor. They will delay paying for the completed work. Of course the content of the website is good but it has severe issues in loading the page.
Now, I am tiered of their poor support and do not want to work for this website anymore