Hi all. I'm a graphic designer myself and planning to buy a Mac Book Pro. I would like to know how much of a difference is there between "Intel Iris Graphics" and "Intel Iris Pro Graphics NVIDIA GeForce GT 750M with 2GB GDDR5 memory"? Because I was thinking to buy a 13" MBP which is easier for me to carry around but if the difference is significant then I may consider to get a 15". Hoping someone could give me some advise. Many thanks.