More/less, I tend to go with an overall feel of the character, ie, how powerful they are, what they are/should be capable of, because, yeah, feats can be very inconsistent, certainly for both PC Supes and Soarin' Norrin. Based on that, and given how outlandishly mighty Boring Swan Superman was (forget the solar-system sneeze; what about towing multiple planets across the universe -- and that he did as a boy!). Writers just went to town with him, trying to one-up the previous stories. I don't see Surfer lasting long against this level of power. I've sometimes wondered how well even Galactus would do against this Superman. He really was demigodlike...except when it came to kryptonite and company.
Given the extreme polar nature of PC Superman, he was also, often, taken down quite easily by anyone with a green, glowing rock. If Surfer uses weakness exploitation (including red sun radiation, iirc another major Achilles heel for PC Supes), then Superman goes down easier than he'd take down Surfer w/o w.e.