I haven't seen these Image Portfolio products before, but as soon as I saw this was Storn Cook, I knew I had to have a look. What the Portfolio is is six images from (in my opinion) one of the finest RPG character artists there is, Storn Cook. I've always loved his character work, and here are six superhero-themed character portraits you can use in non-profit or independent products.
One of the nice things about superhero art is that a lot of it can fit more than one genre.
Two of these pictures I would say are firmly in the Superhero mould - a winged flier, and an electric martial artist (who you can see on the cover). The man in the suit with a fancy sci-fi gun and bionic hand could be superhero, science fiction, or cyberpunk. There's an ogre-mage in a business suit who wouldn't be out of place in a Shadowrun game, a warrior-woman that would fit in with a high-fantasy game. And finally, there's a cosmic being who could be anything from an avatar of the Universe itself to a Cthuluoid horror from beyond the stars.
Storn's character work is dynamic and expressive - these don't seem like "generic" heroes to me. I look at each one and can immediately get ideas for different characters to play.
If I were producing a small-press Superhero-themed product, these would help it look fantastic. Recommended.