Looking to do some 1080p video editing/Photoshopping while I travel for next 11months. Would prefer 13inch for portability but also realise that my travels will end and don't want to limit myself for the future. How much extra GPU power do you get with the 15 rMBP with R9 M370X over the 13 rMBP with Iris 6100? Other than the editing, won't be doing much CPU intensive, browsing and Word docs.