To answer your original question, I had great experience with WLP833 German Bock. It is a little malty for an American Lager, but I really liked the result. Practically sulfer free.
As an adder, I just heard (I think on Brewstrong) that sulfer can be the result of a reaction between your yeast and chlorine in your brewing water. It may just be fresh in my mind, but it was the first thing I thought about when I read your post. It was a little unclear if you have the same issue with ales, but even if not, I have to imagine that different strains react differently in the presence of chlorine.
Are you carbon filtering or using a touch of campden? If not, it might be something to consider.