It works fine for me. I use spaces a bit more now, and have certain programs just assigned for certain spaces, which I didn't do before. And for word processing I hide the top menu bars or go full screen mode more often to capture a few extra lines.
But I don't find the extra space lacking, but I do have a desktop as well -- with a 27 inch monitor for photo editing, etc. That said, for the daily tasks the 11 inch is perfectly fine for me, and I'm almost twice the OP's age and work on computers all day.