Superman with one arm lifted 200 Quintillion Tons. Now Hulk on the other hand, has held the tectonic plates of Sakaar together. However, the forces involved is only in the order of a trillion tons, or less depending greatly on the size of the planet.
Now, this poses a problem as 1 quintillion tons is a million times greater than 1 trillion tons, meaning Superman is lifting 200 million times more weight with his one arm.
Superman showing no signs of an upper limit and while the same could be argued for Hulk. This is not one of Superman's better feats, where this is arguably Hulk's greatest feat.
There are dozens of accounts of Superman moving planets and moons, all ranging from 81 quintillion tons to 6,600 quintillion tons.
In the past Superman has also:
- Simultaneously moved dozens of planets from one side of the universe to the other.
- Moved a planet 6 times the mass of Earth under a red sun (which weakens him).
- With the aid of Wonder Woman, lifted half the weight of the eternity
- Contained a micro black hole in his hands for a period of time.
- In New 52 he bench pressed the weight of the Earth for 5 days straight while cut off from the Sun (with little effort).
It's safe to say Superman is considerably stronger.
In a low end/high end comparison, Superman's low end is some billion times greater than The Hulk's high end.
Marvel states that Hulk has never shown an upper limit and stated that Hulk's strength is not limitless (these statements are not mutually exclusive). There are numerous in comic statements by other characters suggesting that Hulk may not have any limits. However, there are several instances showing these character statements as false (even if they weren't demonstrated to be false, it's a blatant no limits fallacy).
Four of these instances include; his fight with Sentry, an early fight with Juggernaut where Dr. Strange intervened before Hulk was killed, a fight with a weakened Juggernaut where Hulk was enhanced BEYOND his normal limits by Apocalypse, and his fight with Onslaught where Phoenix pushed Hulk to his maximum anger level.