I think they might be nice for safety alone, but I'd forget about using it in place of side mirrors to cut wind drag. You'll probably be gaining hundreths of a mpg. The difference won't even be measurable.
As far as legality, I'm not sure, and it's probably a state law anyway. I used to drive an old Jeep Wrangler that only had a side mirror on the driver's side. Most of the time I didn't even have a rear view mirrow. I never had anyone give me any trouble about it though.
Scouring the country for an excellent condition Civic VX
Wow, that's interesting, but most laws like that are not give and take, as are the pollution laws. I think mehbe you should be able to switch around mirrors, but not buy the right to pollute, but whatev.
i have a razo wideview mirror in my car and its nice, but it is illegal in all states as far as i know to remove both mirros. minimum is the driver's, but i think thats only if your car had the option to only have one from the factory. ie, 92-95 civic cx etc