My favorite brand is Ritter Sport. Especially the peppermint stuff they offer.
Considering the fact that they have a factory sell-out like 15 minutes from my place a always have some at home

One of the most interesting tasting chocolates I recently had, was Lindt. A very dark chocolate (70% cocoa) filled with Mouse au Chocolat and a mixture of Cherry and Chilly. Sounded very strange to me, but turned into a delicious chocolate.
Probably the best chocolate I had was some brand from Switzerland I cannot remember.