Regarding the Baker's chocolate as a doorstop... I actually just read in an interesting article (Link: http://www.sfgate.com/cgi-bin/article... ) about which bittersweet chocolate was best for baking. They also rated best for eating.
Bakers and Nestle Chocolatier won (Nestle 1st and Bakers 2nd) the baked-in brownie recipe! I was pleasantly surprised as I would not have expected that at all. Lindt actually won out in the tasting contest. Again, a surprise. Sweet Earth did best overall.
I think when baking it is important to keep in mind that chocolate needs to be formulated for baking to achieve best results. Any chocolate you love the taste of purely on that premise alone would probably work best for a recipe with no baking involved.