Rokinon 35mm f/1.4 which version to buy??

Im planning on buying one, but dont know which version to get. Since they dont make a NEX version, ill need to get an adapter ether way. Amazon sells the Olympus version for $100 cheaper then the others. Should I just get that and a 4/3 to nex adapter??

My main concern is that the Olympus version is a 4/3 format lens and the others are APS, would it cause any issues with the optics and or quality??