I have been with FC for several years. Over the years, I have not been credited more times than I can count. I am not even interested in counting those times. I also have had some payments revoked, but not very many. In some of the situations where I did not get credit, it was because I used safari which, some years back, was a problem because some offers were built just for windows at the time period. It may no longer be a problem. I long ago began to use chrome.
However, when it is all said and done, most of my offers did credit. I have had a lot of fun on FC and I have made enough money to use towards extras in my life that added to the quality of my life.
I am unhappy when offers and surveys don't credit or when a payment is revoked but FC is still the best site of its kind, at least in my opinion and I move on. The next survey or offer will probably credit and maybe next cashout, no payment will get revoked.