I do not have a favorite site, as much as I have a favorite type. I like the sites where you get to choose your path, such as satoshi mines and such. These sites are more interesting, because you get to make the choices to determine what your fate will be.
In fact You can do the same with gambling also , There are some sure matches also which are deeply analysed and odds are very low for them like ATP rank 1 Playing with ATP rank 200.