My only issue is the screen size. On a regular day, I am 60% time on my Air. Which will mostly be replaced with a Surface 3. The Air 13" and I don't know how small 10.8" really is. Help?
Hmmm, it would be tough for me to replace a 13" laptop with a Surface 3 if that were my primary productivity device. I'm not sure what your other criteria is, but if you're comfortable with the size of the Air you might want to look at the Surface Pro line. Additionally, you're definitely going to notice a performance loss by going to the Surface 3. (again, I'd look at a Surface Pro 4 if I were you)