I've tried a few of them and they work pretty well overall, though I don't have a ton of experience with their line. The only ones I've tried are Donut, Poundcake, Cookie and White Chocolate. I wasn't a huge fan of those four and I LOVE pound cake and white chocolate - that was the primary reason I bought those two. The taste simply wasn't there.
I'll be giving them a second look, but so far, I'm not too impressed with the ones I have right now.