Yeah, I didn't realize until I tried it that it is going to people rather than an algorithm.

I tried FlightFox twice, and both times the CEO Lauren (who is fantastic at customer service) refunded my fee because I was able to find better flights cheaper than the 'experts'.

I just don't see how any of this works as a real business model, but something must be working because FlightFox is still at it years later.

Almost exactly but not as good. FlightFox doesn't make you link to the ceiling price, so you can pick a price you don't want to go over and then you don't pay if they can't help you. While Flystein makes you prove your price with a link, which isn't all that easy considering that many rates can't be deeplinked.

At Flystein we ask a link OR a screenshot in case of Beat My Price so there is no problem here. Also you could just specify some realistic budget in the text description with Build My Trip option and you are very welcome to try our services :) Cheers!