My favorite chameleon was my sambava panther chameleon who was the nicest, friendliest guy I've ever had. My mellers and temporalis pygmies were very neat too. The mellers was a mean guy though.
By far Calumma parsonii. Other ones that were extremely neat to work with are K. matschiei (Giant Fischers), T.deremensis, T. quadricornis and T.melleri. For smaller chameleons Trioceros montium and want to work with Bradypodion species in the future.
It is kind of tough to label best chameleon as I'm for the most part a fan of them all.
My cap est are my most rewarding so far, I havnt owned them Long but there my first WC panther chameleons and I already have fertile eggs cooking so there doing well, just the fact that there wild caught makes me love them