I'm currently using a 2011 Macbook Pro 15" and I love it. However, for my needs, I definitely could get away with a Macbook Air. My biggest concern is whether or not it will "feel" like a downgrade to go from a 15" screen to a 13" screen. I realize that my web browser or any office docs will likely use a greater percentage of the screen (right now my browser/office windows usually take up maybe 70% of the screen on my 15"), but will I really feel like I have a lesser computer? Thanks for any input, especially from those who have gone from a 15" to a 13" computer. I'm also considering buying an external monitor for the moments when I do want to multitask with multiple windows open.