I don't do lunch time workouts very often, but when I do I feel great. There is something about escaping for an hour and letting yourself relax and maybe even relieve some stress. Sometimes I do classes, but even 20-30 mins on a machine is great.
Some days its the only way I can make sure I have time to get it in.
What time do you work out and why do you like that time?
Just some food for thought ;)