Hi, I'm thinking of purchasing a base 13" MBA with 8 gigs of RAM. This would be my only computer, and in addition to basic usage, I'll need to do some work with Photoshop, Illustrator and InDesign (CS6). A few questions I have: 1. How does the 2012 MBA perform when using these apps with no external display? 2. How do these apps perform when using a Thunderbolt Display? How is the Air's performance with a Thunderbolt Display in general? 3. How is the quality of the Air's own display? Is text crisp and legible on the 13" screen? How are colors? I will be using the Air with no external display a fair amount of the time. 4. For my purposes, would upgrading to an i7 make much of a difference? Thanks in advance for the help!