If you don't run 3d games, go for it.
Buy a monitor for use on your desk, and enjoy the smaller form factor.
I chop and change form factor on my work laptops on a regular basis (i'm IT, and part of my job is evaluating hardware) - currently i have a 12.1 machine at work hooked up to a 22" monitor and it is fine going between that an my 15" pro at home, or the 15" machines I had previously at work.
Also, my ex had an 11" MBA, and that was fine for most stuff, and certainly much more convenient on the move.
The 12"-13" form factor is a lot more convenient to carry with you, use on aircraft (15" is just not usable in economy), etc.
Have you considered a 13" MBA with 8gb instead of the 13" pro? You'll get an SSD in that, 1440x900 screen like the non-hires 15" Pro, etc...
Buy a monitor for use on your desk, and enjoy the smaller form factor.
I chop and change form factor on my work laptops on a regular basis (i'm IT, and part of my job is evaluating hardware) - currently i have a 12.1 machine at work hooked up to a 22" monitor and it is fine going between that an my 15" pro at home, or the 15" machines I had previously at work.
Also, my ex had an 11" MBA, and that was fine for most stuff, and certainly much more convenient on the move.
The 12"-13" form factor is a lot more convenient to carry with you, use on aircraft (15" is just not usable in economy), etc.
Have you considered a 13" MBA with 8gb instead of the 13" pro? You'll get an SSD in that, 1440x900 screen like the non-hires 15" Pro, etc...