City water and sulfur smell....do you have a house filter? Usually city supplies have chlorine added to the water to kill/cut down on water microbes. Some filter systems filter out the chlorine and allow the microbes to breed in the water heater, on the anode rod and create a sulfur smell in the HOT side only. This can be overcome by either a different or better filter or specifying an aluminum anode rod.
Sorry, I've got no experience with BW heaters but they seem to be preffered on this site.