It depends on how early I wake up and how much sleep I got.
For the last two years, especially after this past November, I was getting about 3-3.5 hours of sleep a night during the week since I had to get up so early, yet I'm a night owl. (As an example, last night I was so exhausted when I got home that I kept having "micro sleep-outs" while typing on my laptop on the bed, I'd wake up after a second with my hands depressing the keys -- yet about 10-10:30pm, suddenly I started feeling more and more awake. Drat.) Sometimes I had trouble making the one-hour drive to work, sometimes I was fine, but I'd have some rough periods during the day lasting about an hour or more where I'd keep nodding off or feeling like I wouldn't make it through a meeting.
With my recent move, even if going to bed at midnight, I can get 5+ hours of sleep and am feeling better overall already.
I like mornings in the sense that it's pretty amazing to have a lot done by lunch, and based on my work schedule, I'm hopping in a car to come home between 3-3:30pm. However, I'm not really a morning person and need my caffeine to keep me going; I'd rather stay up until 3-4am and then crash.
I'm 43 now, and I find that I become sore more easily and longer / can't handle as much stress on my body (especially without training) as I used to. I'm feeling older, physically, definitely. I'm currently out of exercise but plan to start back up now that I've moved and can sleep enough to get my energy levels higher. When I'm exercising consistently, I actually feel pretty good.