9.5mm is rear wheel for semi-wide bodies, is was later replaced by -1 offset 11mm wheels, i.e. equivilant to 10mm from hub. and the semi-wide was discontinued.
i didn't know there's a 14mm wheel, if u're referring to the atomic one, it's a -1 offset 13mm wheel, i.e. equivilant to 12mm from hub. and it's for more traction at the rear that i don't think is necessary.