I really can't say either. I haven't read any of the Legacy books, or the Marvel comics for that matter; but what of her one apprentice? Who - from what I read - had trouble levitating an orb no bigger than his fist. Plus, she would've lost a decent amount of Force power when she was turned into a cyborg.
Also from what I know, she was defeated by Luke. And that was Luke just after ROTJ I believe.
Anyways, wasn't she even training a damn YZ? Yeah, she's powerful (or grown more apparently), but I'll fall with the default position of Obi-Wan. I think he [of anybody] has the experience, and skill to beat her. Her lightwhip is another factor to consider, but Obi-Wan has dealt with unorthodox methods of fighting (GG).