Well then I'm going to keep my answer, but I'm not sure. There are no real big force users, but I'm tempted to say Aayla is the best. I don't know why, just a hunch (which counts for little). It would be a tough fight but The duo would probably win. Unless Ventress could throw one away and beat down the other repeatedly, then she would probably lose. That probably wouldn't happen though, because both teammates are solid contenders.
Ventress gave Anakin a hard time who had to literally tweak right out in order to defeat Asajj. She almost outdueled Kenobi and she whooped Fisto's ass.
Aayla is fairly good, but she isn't a very good Duelist, to be honest.
Aurra is a good Lightsaber user as well, but she should stick to guns.
Asajj walks out alive, but injured.