"Whether it's everything we might have asked for is still a question worth pondering, but the clenched weight of the thing is often staggering while it's above you."
Robey went on to say the film could use a sense of humour in its 143-minute run time, saying it needed to "inject some wit".
He gave it three stars out of a possible five.
Charlie McCollum from the Mercury News agreed, calling it a "smart, nuanced take on the Superman mythology". He also called it "relentlessly grim".
"It successfully tweaks Superman's now-familiar origin story to make it more complex and more interesting. In addition, it carries enough visual and action punch to succeed on that level."
Associated Press reviewer Jake Coyle said the film was far too "solemn" for his liking.
"Snyder's joyless film, laden as if composed of the stuff of its hero's metallic nickname, has nothing soaring about it," Coyle wrote. "(It) goes more than two hours before the slightest joke or smirk."
Todd McCarthy from The Hollywood Reporter was more positive, praising the film's action set pieces, the script - which was co-written by Batman director Christopher Nolan - and Hans Zimmer's score.
McCarthy said the film "should remain firmly planted around the world for much of the summer".
"Man of Steel ... serves up what could be as much spectacle and action - minute-by-minute, frame-by-frame - as any movie anyone could think of. Zack Snyder's huge, backstory-heavy extravaganza is a rehab job that perhaps didn't cry out to be done but proves so overwhelmingly insistent in its size and strength that it's hard not to give in."
Elsewhere, Guardian reviewer Andrew Pulver gave Man of Steel three stars with the critic highlighting a "damp squib" of a relationship between Superman and Lois Lane, played by Amy Adams.
"The failure to cook up much in the way of meaningful interaction for the pair throughout the film's mid-section means that Man of Steel begins to labour even as the visual spectacle intensifies: no amount of whip-pans and crash-zooms, spaceship flameouts or collapsing edifices can compensate for an inert focal relationship," Pulver wrote.
And the New York Daily News called Man of Steel "flawed".
"The serious-minded result has many super-cool moments. But when it gets clunky, it's super-meh," said reviewer Joe Neumaier.
"Man of Steel has flaws it can't overcome."
- nzherald.co.nz
