Exar Kun and Ulic Qel Droma vs Darth Vader and Count Dooku ( lightsabers only )

Which makes his stalemate with Ulic more impressive. Before getting his Saber-staff he was equal to one of if not the best duelist of that era.

He didn't just adopt a saberstaff though, he began using ancient Sith techniques, those he discovered in the Dark Holocron. Thus he's adopting the kind of fighting styles that Kreia masturbated over and which apparently made Tulak Hord a Jedi army buster.