How far was the Surfer away from Thanos when he had the gauntlet? how long did it take him to reach that distance? What exactly is the end of the universe in terms of distance or light years? One feat can be measured, the other simply wasn't.
Hold on a second. You don't know how far it is and still give the Flash the win handily, while the Surfers feat was actually measured? i don't even think that the Flashes feat can be or should be brought up, because of the fact that it is not quantifiable. Perhaps another feat of his should be used? One that is actually quantifiable?
It's like saying Hero A can lift a lot, while on the other hand saying that Hero B can lift a trillion kilos. You see what I'm getting at?
One light year. Source wall is at the end of the universe which is about 46 billion light years according to current estimates.
To even pretend that Surfer's feat was better because the distance was given is utterly laughable. Going from Source Wall to Earth is FAAAAAAAAAAAAAR more impressive than going a light year in a second or two. Nobody sane would argue otherwise.
But I did give you a quantification: the end of the universe as we currently know it. That's a rather humble estimate, but it's fairly above everything Surfer has done.
If you want a ever lower quantification, I can look into past DC comics that talk about different galaxies, such distance can be mesured and would still be considered closer than the end of the universe. It would also dwarf Surfer's feats.
You're falling into the trap of thinking that the feat being unquantifiable means there is no valid comparison to make between this and other feats. Hulk can have "unquantifiable" strengh, but we can surely accept that he's stronger than Captain America when he's lifting an imaginary moon.
Running to the source wall is impressive. Offhand, I don't think the Surfer has anywhere near a comparable feat (covering several million lightyears in seconds? That's practically teleportation). But...is the source-wall run an outlier? What's the Flash's next best feat?
Surfer may be more consistent (btw, I once did a ballpark calculation of that Surfer-Thanos-CaptainAmerica feat, and it came out to about 300 megacee).
Shinier than a speeding bullet.