I purchased a MBP15 a yesterday and it seems too big right now, I have the option of switching to a 13" but after tomorrow I can't because I'm leaving the US for a month. Everybody keeps telling me that the machine is massive, humungus, big etc. compared to the 13" and I will have to carry it to school everyday. The 13" screen is fine for me but I'm not sure about the power. I game moderately with games like Fallout 3, Counter Strike Source and CoD4. Any opinions? Should I keep it and lug it around school or get the 13".