Man of Steel, and it isn't even close.
I walked out of Returns trying to convince myself how much I love the film. But the only things I liked about it were the VERY few "action" scenes like him getting in the eye with the bullet, him saving the plane and getting a standing ovation in the stadium, the audio cuts of Brando, him flying through Metropolis catching the Daily Planet globe, using laser vision to melt falling glass, blowing out the sewer-fire, and him falling to earth while people watched after he lifted the contient. In total all those scenes probably took up less than 10 minutes. I actually saw Returns a bunch of times in theaters and found myself bored except for THOSE scenes.
Other than those few scenes Returns was a snorefest I tried really hard to love, but never could.
With Man of Steel I actually walked out initially disappointed, and then (because I had the RT critics in my head) I tried to poke holes in it, but started to come up empty.
So with Returns I was trying to find excuses to love it.
With MoS I was trying to find excuses to hate it.
Returns got less appealing overtime
MoS is becoming more appealing the more I think of it.
Also, in many ways the best scenes in MoS aren't even the action scenes necessarily. Like I'm not going back to see it in Theaters just for action sequences, I actually want to see the plot and dialogue all over again. Hell, the scenes BEFORE Clark puts on the suit in MoS are some of the strongest to me, that wasn't true for Returns.