i'm a graphic designer(digital painter) needing a computer that can run photoshop smoothly in big resolutions. having owned and barely touched either macs or laptops before i'm taking the plunge for a mac laptop. ive got a few questions, bear with me if they betray my lack of experience, i would rather be sure considering how much ill be shelling out. non-retina MBP 15" 2.7ghz aftermarket: 16gb crucial RAM and 256gb crucial m4 SSD would pop the stock hdd in an enclosure and have it external for storage. rather than get the retina i am investing in a 24" dell ultrasharp U2410 monitor to use externally at home when i am working. i wont need the higher resolution apart from when i'm working and i would like to be able to upgrade it in the future if i needed to. my questions are: 1. what are the advantages/disadvantages of a 2.7ghz processor considering i also have the option of a 2.3 or 2.6? as i understand it the SSD and ram will make a bigger difference, i have the money saved up so the price isnt an issue as much as the potential of overheating, or too much noise etc. 2. how much will running a macbook in closed (or even open) shell through an external + an external hard drive affect the battery / heating? thanks.