I have a lot to lose but I have now lost 14 pounds with what seems like very little effort and the fast days are becoming easier. I do high intensity interval training 3/4 times a week and haven't noticed any problems when I exercise in the morning after a fast day.
My shape and inch loss seems to be improving faster than the amount of weight lost would indicate and people are starting to notice.
Still a long way to go and it is no crash diet or quick fix but it feels effective and sustainable and sane