Provably fair was created mainly to ensure that dice sites are reliable!
That's true, but I'd still stick to more established and reputable casinos. Provably fair doesn't guarantee you will be allowed to win and cash out.
It's easy to implement provably fair function and then take people's winnings and close the site down.
But if anyone knows how to run this gambling business will not try to cheat people for small profits because these guys knows in the longer run they are going to win and they can make a good money from this business. So most established sites and some of new sites also will not do any cheating but we just need to choose the correct one.
Alot can be made in a quick roll of the dice and they just use those losses to throw back into their casinos bank roll waiting for the next one waiting in line to do the same. It is brilliant concept if you stop to think of it.