Unfortunately, it's not as simple as LC vs SC with the NEW. It's more common for the Long Combs to have the smaller slots (I've heard it's typically older ones without the patent numbers) but I've read some people have found short combs that have the smaller slots too..
Ya things can get pretty complicated with handle compatibility. As well as differences between the particular year of manufacture, there can also be small but significant variations between different countries of manufacture of the same model. I have a CanadianTech that for some reason, won't accommodate other Gillette handles...
