I think you forgot the solid state drive. Honestly I would have just paid up for a large external monitor and a solid state drive for the 13" MBP. Xcode is sooo

I think you forgot the solid state drive. Honestly I would have just paid up for a large external monitor and a solid state drive for the 13" MBP. Xcode is sooo much nicer with a lot of RAM (check) and a solid state drive but maybe you are getting enough performance boost from the striped drives. I doubt it though. EDIT: Also, I hardly ever use the retina simulators since they get in the way and you really need the device to get a good feel for how an apps feels so I just test on actual devices so you could spend the $1k on those instead too. All that said the 15" MBP is a solid machine. I have two.