So I've now used two different kinds of paint: the standard Behr paint and the No-VOC Freshaire, both from Home Depot. Smell-wise, they both did. Probably about the same amount. I was expecting to be overwhelmed by the smell of the regular paint, but it really wasn't that noticeable or bothersome. However, I know that no-smell is not the same as No-VOC, so I will try to use a less toxic paint in the rest of the house unless I find a color I can't live without.
Coverage-wise, I was, again, pleasantly surprised by the Behr. I was sure I was going to need three coats for the bright Cool Lava/coral color. However, after two coats (on top of one coat of primer), the walls looked great. In the other two bedrooms, I felt the Freshaire's coverage was not so good -- even though I was using light colors, I still applied two coats. Maybe I would have anyway though, because it does seem like that's what it takes to get the full impact of the color.
I really like the two-tone wall technique. Well, I like the results of the technique; actually going through the process is a bit of a drag. However, it seems like a good solution for rooms where you want to use a strong color but need to decrease that weird contrast that happens between colored walls and white ceiling. Since we have ugly textured ceilings with jagged edges left behind by wallpaper removal, I like to create as little visual interest up there as possible. I think I may try this again in the living room. After a break. :)