Sorry, I haven't had them--if I'm going to consume that many calories, it's going to be something I like better, such as chocolate! I searched all the CH boards for "whole food marshmallows" and saw a few positive references, if that's any use.
Holy carp! I didn't know this place existed. I'll have to check it out. I got some marshmallows from WHole Foods and they were pretty good with some nice hot cocoa, but I'm definitely still looking for something better.