I've used UserTesting.com for previous tests. If your product affects a lowest-common-denominator user or you are testing mainly UX/interaction, I'd recommend i

I've used UserTesting.com for previous tests. If your product affects a lowest-common-denominator user or you are testing mainly UX/interaction, I'd recommend it. At that time I paid around $20 per usability test (I bought a packet of multiple sessions). Testers recorded using my product for 5 to 10 minutes and it was great watching them stumble over what I had designed. They were also trained to be over-communicative and think aloud, which really helped. In total I did four or five of them before I had my first release (since it was still somewhat expensive, I tried to ration my tests by fixing all previous UX bugs before issuing another one). It's been a long time, but if I recall correctly, a few times the testers weren't tech-competent enough to actually do the test, but when I asked UserTesting for a credit or refund to re-do the test because the tester was "bad", they provided one without hassle. You need to be make it as easy as possible to run your user test, because a tester will give up on roadblocks that take more than 60 seconds to solve. I was developing a language learning product, and so needed testers who were interested in language X. In the end, the people I found using the filter [Interested in X language, native English] weren't actually interested in language X. Rather, they came across as people who had accepted the filter to make an extra buck. However, it was good enough for a random internet trial. If I wanted better results I had to do it in person (which I also recommend).