Originally posted by Jmanghan
What book was he compared to Katarn as a duelist and fighting evenly with Mara?

He was good; Luke gave him that. He might have been a match for an expert swordsmaster such as Kyp or Kyle Katarn. He would have been too much for a comparatively diffident duelist such as Cilghal, or even Luke as he had been back at Sinkhole Station, at low ebb in physical and mental strength.

Source: Fate of the Jedi: Backlash
From Nova's RT

He fought evenly with Jaina in Dark Journey.
Here is his RT: http://comicvine.gamespot.com/profile/shootingnova/blog/kyp-durron-respect-thread/100235/