Bartneck, C., Duenser, A., Moltchanova, E., & Zawieska, K. (2015). Comparing the similarity of responses received from studies in Amazon’s Mechanical Turk to studies conducted online and with direct recruitment. PloS one, 10(4), e0121595.
There are certainly high criticism on MTurk but somehow it have some validity, but I would advice to avoid it rather trying to check its validity by yourself.