Though I read the thread rather quickly, did not see you describe the flavors, only that it "tasted horrible." I am likewise struggling with a hefe brewed with the Danstar dry yeast; it has really bad plastic flavor that makes it undrinkable. It was very slow to start - four days - and then fermentation was extremely slow (3 weeks) and even while fermenting, smelled of plastic and cleaning fluid. Two other times I have had very good hefes using White Labs liquid; this was the first time using Danstar munich dry and, coincidentally, 100% tap water. Anyway, I am interested in what yours tastes like, if we perhaps have the same off flavors and maybe can point to a problem with the yeast.