In HSDS, Zhang Wuji safely "caught" people who jumped down from the 10th floor of a pagoda (so, let's say 10 zhang). He used the Great Universal Shift to convert the energy from their fall to a horizontal "throw" to the ground. He did this repeatedly for all the imprisoned martial artists from the 6 major sects, I'm guessing 30-50 people? It was said that this temporarily depleted his internal energy, even before the retaliatory strike from Miejue.
In DGSD, Murong Fu did a similar vertical-to-horizontal energy conversion to Xuzhu and Tianshan Tonglao, who fell from a several hundred zhang mountain (数百丈高). This almost knocked MRF out, so wasn't easy for him. Although Xuzhu got some extra help by landing on a poor fellow's belly followed by Duan Yu's repelling energy, I believe Xuzhu (or any martial artist worth a salt) could have landed safely using his own martial arts, just as the heroes of HSDS were able to.
Do you think one feat is more impressive than the other?
Can they reproduce (or improve) each other's feat?
I think MRF's feat is pretty impressive for his level. He had to handle two subjects falling from the equivalent of the ~300th floor of a building. That's about 30 times taller than Wuji's subjects. I think it's worthy of Tianshan Tonglao's "superbly adept" praise.