That's the thing, a Retina Pro is about 15 - 20% overall bigger/heavier; in some parts the dimensions are the same, and in other parts it's even slimmer. Far more power - literally double RAM and CPU. Iris graphics FTW too.
running the fnb deal - ME865 - rmbp 256gb/8gb. perfect for my usage. personally not enough storage. want to run parallels (win8). next time 512 one rather. would like 16gb ram though.