none of those OEMs make a good notebook at 13 (except the xps 13, which is an ultrabook), you probably may find the sony s13 a good bet, since it packs a 640m LE inside the chassis that is around the same thickness of the cmbp 13 and with the weight of the rmbp 13, though it has its drawbacks
Yea, like the fact that you have to use Windows