I have got boar, various variety of badger hair brushes and a few synthetics. They will all lather up any cream, croap (soft Italian soaps like Proraso) or hard soap I want to use. They all do the job but need slightly different techniques to get the best out of them and they all have a different feel on the face. From the ability to make a good lather POV I'd have to say there is no best. There is a best but that would depend on what you like in a brush and the only way to find that out is to try a variety of them.

Bob