I've never seen a price difference in flavored v. natural myself... I guess I dont really use unflavored though (I cant imagine its palatable)
The whey they sell here(Grow!) is not "flavored" per se, but it has a hint of sweetness to it. The Metabolic Drive (which is a mix of whey, casein and other kinds of protein) taste GREAT for the most part. I very rarely hear someone complain about the flavor.