I am at the grouting stage of my project. is epoxy grout the best stuff to use for granite? And how do you clean it off the stone?

If you're not familiar with epoxy grout you should consider hiring someone experienced.
Nothing is (best) for a granite tile .... it depends on the whole installation and where the installation is.
If it's a residential floor with small grout lines then unsanded (portland) grout is fine. Sanded can be used on wider lines (wider than 1/8").

Epoxy can be used on counter tops where sanitation may be a factor. I use epoxy on almost all counter tops.

Thanks for the advice. It is surely valued. Loren