Although Kiu Fung and Kau Mor Tze never directly fought each other during DGSD, most wuxia fans judge them to be approximately equals in terms of overall martial arts ability. Wuxia fans generally accept this idea because despite their not having fought each other, Kiu Fung and Kau Mor Tze performed similarly well in fights against various opponents (Mo Yung F'uk, members of the Great Evils, etc.).
At the Heavenly Dragon Temple in Dali, Kau Mor Tze was able to hold his own against the 6 Mak Divine Swords of the temple's monks by using his Flaming Hand Sabre technique. Said technique, true to its name, expressed Kau Mor Tze's inner power in the "structure" of a flaming sabre that shot out of the side of his hand...and was well-suited to meeting the "sword"-shaped "structure" of the Heavenly Dragon Temple monks' 6 Mak Divine Swords inner energy streams.
One would expect that Kiu Fung, as a martial artist on par with Kau Mor Tze, would do equally well...but would he? Unlike Kau Mor Tze, most of Kiu Fung's best skills were close-in, melee combat techniques (e.g. Dog Beating Stick Technique and various Shaolin hand-to-hand techniques). His one legitimate long-range inner power attack was the Hong Lung 28 Palms. The power of Kiu Fung's Hong Lung 28 Palms is well-known, but is the *structure* of Kiu Fung's inner energy as expressed via the Hong Lung 28 Palms as well-suited to meeting the energy of 6 Mak Divine Swords head-on as Kau Mor Tze's Flaming Hand Sabre energy was?
Despite their overall parity, Kiu Fung seemingly might not have done as well against the Heavenly Dragon Temple monks as Kau Mor Tze did...at least if 6 Mak Divine Swords come into play.