My only other Master-Cleanse experience was a 7-day "trial run" last month. The horrible detox symptoms taught me a lesson, so that's why I did a pre-cleanse this time. I'm glad that you look at the inevitable detox crises coming up with such a positive attitude.
The 20 days on fruit and raw veggies also forced me to really focus on the upcoming 40-day MC, hold it in my awareness and give it more importance. It helped me to be more committed.
I've been needing more naps myself. Napping is healthy and probably part of adjusting, but I also think I haven't been drinking enough lemondade so far - I'll try to increase my intake.