The 3200 has thicker cross hairs. 4200 has pretty decent cross hairs. Not near as thick. Glass is about the same, Eye relief, the same.
I think the eye relief on the Elites is really awesome actually.
I just took 2 rifles out yesterday to compare. 3200 5-15x40 w/ao mildot and a 4200 4-16x40 with ao multi reticle. Other than the thickness of the crosshairs I like them both.