13" rMBP v. 15" rMBP

Hi guys,

So I'm looking to get one of the new retina Macbook Pros, and I wanted to get your opinions on the size. If I were to get the 13", I would likely get the highest-level model (2.6 GHz i5, 8 gb ram, 512 gb ssd). If I were to get the 15", I would get the lowest-level model (2.0 GHz i7, 8 gb ram, 256 gb ssd). I would really like to have the extra graphics power on the 15", but since the Verge reviewed the model with a discrete GPU, I'm not sure if the bump in graphics performance would be significant on the lower-level model. Also, I don't know if the gains would be worth the larger size/weight and lowered battery life. Any opinions or general debates about which is better (especially as there's only a $200 difference),

Any help is appreciated!