GSP IMO had a more impressive run at WW than Fedor did at HW. Not by a lot, but I think the competition GSP faced p4p was better. Now for why I think Fedor is better p4p. Fedor became the GOAT HW and not many dispute that, but Fedor is a natural LHW. Fedor dominated a weightclass that he really didnt belong in, while GSP did not face a single fighter bigger than himself. Just imagine GSP being as dominant, but at MW. What Fedor did puts him p4p well above anybody else.