This one's really good. I want to start with that right away because my impression after the first game I ran was actually negative.
I ran more ICONS games since then, and I gotta say that once you know how to use its narrative-driven rules, it works VERY well.
So the short review is: If you want a superhero RPG that feels just like the comics do, get this one.
And now for a more complete review:
This is the one superhero game I know of where characters of different power levels can play together and it still works. I'm not saying it's always perfect, but of all the superhero systems I have played, this is the one that can actually make it happen. (I'm not claiming that it's the only superhero system that accomplishes this as I haven't tried them all.)
During my initial negative first impression I complained about the apparent fragility of heroes without physical powers. I didn't realize at the time that the system allows every character to narratively replicate such powers via the Stunt system. (A character hiding behind a tree, for example, replicates having armor, etc.) So this system actually makes it possible for Batman to single-handedly stop the White Martians...
In this example, Batman took a Page of preparation and used his Gadgets power (Simple Gas and matches in this case) to replicate the Nullification power, taking away the powers of the White Martians. Story-wise Batman's player uses the White Martians' weakness to fire to accomplish this, since all of their powers have the 'Blocked by Fire' Limit. One could argue he used two Pages to also replicate Binding so the White Martians couldn't go anywhere, as they are surrounded by the fire. As for how he deduced their weakness, he probably used his 'World's Greatest Detective' Quality.
While also leaving the possibility of a normal human knocking him out. And it all works with the same rules.
Here, a criminal knocks out Batman with the butt of his gun. Either he managed to attack Batman by surprise and so the Dark Knight couldn't react and took the hit like a normal human (his cowl was not armored back in those days) or the GM actually informs him he's been knocked out by surprise without any dice-rolling and gives the player a point of Determination to use later if Batman's player accepts the Trouble.
So already just in that regard, this is very comic-book-like. I love it, now that I understand it.
I'll just throw two disclaimers though;
1. Any players who struggle with what to do on their turn in games where the options are pretty simple, and/or who need to have a specific and complete list of what they can and cannot actually do, might actually have trouble using this system to its fullest. To be blunt, that will be more of a player problem than a system problem, but it's still relevant to point out.
2. It is a PAIN to find rules in this book. Looking for how to do something will send you back and forth through the book because many rules are used in unison. There are no specific pages given for where to find rules either, just whole chapters. The good thing is that once you know them you don't need to look up in the book that often because the rules are not difficult per se, but for the first few games where you simply don't remember all the details, expect a few pauses in the game to look up how something works, and to be looking for it longer than you would have with a more complicated system. I find that ironic.
GMs, you know your group. I think most players will love the fact that they can come up with new ways the use their powers on the spot, or argue about how their story-centric Qualities might affect the narrative and/or give them a bonus in certain situations. It also encourages the players to accept setbacks and you'll even have occasions where players themselves point out flaws their characetrs have and suggest how it could work against them because they will be rewarded for it with Determination points. (Which they can use to their advantage later on.)
I think most GMs will love that coming up with NPC stats is ridiculously quick. I can, no joke, create a bad guy NPC with really complex super-powers in maybe 5 minutes, and that's including the time it takes to write down the stats and such.
ICONS is now my go-to game for superhero RP. I don't feel bad about my initial first impression because I do think it's a mistake in the book's editing, where it didn't make things easy to find, but nevertheless now that I am familiar with it I cannot recommend it highly enough.