I know US models W123's used H6024 sealed beam halogens, but Phillip's offers an H6017 unit. It says that it replaces the older 6012/6014 incandescent lamps as well as the H6024. GE, Sylvania, Wagner, etc only make the H6024 unit. So is the Phillip's H6017 really an upgrade over the H6024? Both my lamps burned out this summer and I replaced them with GE H6024's. But now I found the Phillip's lamps on sale and I'm thinking of buying them. Also I was wondering if any of the manufactures offer long life versions of the H6024?