Pros: doesn't pollute, zero VOCs (no toxic fumes!), infinite colors, good coverage
At about $44/gallon, American Pride is cheaper than any other eco-friendly paint that I priced, and my local eco-friendly home furnishing store (EcoHome Improvement in Berkeley) can create any color for me. Some brands (like Yolo) come in a set number of pre-mixed colors, limiting consumers to the company's palette; not American Pride! They have every finish: matte, semi-gloss, full gloss, exterior, you name it. Right now I am sitting in my sunny yellow living room (American Pride mixed to a matte sunflower yellow) which soon will have glossy cream-colored trim.
It's even saving me from the hideous sea-green kitchen that my rental house had when I moved in. Thank god for landlords that let me paint. (Nice for them, huh? They don't even have to pay for the paint.) I seem to remember that it is even cheaper to get quarts of American Pride's colors, maybe just because you can get less paint and not have quarter- or half-gallons sitting around - but maybe because it costs more to custom-mix. They have good coverage, too; the folks at the store warned me that especially with light colors, I would probably need several coats, but so far one coat has satisfied me in the living room and my bedroom.
My only caveat would be to suggest using semi-gloss or glossy for interior walls if you don't mind the way it looks. I like my matte finish just fine, but I went with it because I thought the walls wouldn't get dirty ("oh, I can just paint over any dirt, anyway!") and let me tell you, my walls get scuffed up. Somehow I seem to get everything from dirt to dinner on them, despite the fact that the sofa is the middle of the room. And matte paint is not easy to clean; you're more likely to clean the paint off than just the dirt. Word to the wise!