My clubmate did the National 24hr this weekend, and had to pull out after 16hrs with stomach issues, I have no plans to do a 24hr, none at all!!!!.
The 12 I could manage, our district 12hr course is a stones throw from my house, and my missus said she'd do all the support, which is a bonus.
Your times are very good, you must be winning plenty of prize money with those!!!, I've only won £20 since I started late last year, although I came 8th on a 25TT, 13 secs off the prize money!.
I find riding fits in with my lifestyle so much better, its much more of a social thing too, I always thought I didn't fit into the "running set", but I find myself much more at home in cycling, plus I cycle to work, so I can combine training with saving fuel!.
Agree about the wind, although I am pretty big and strong, so I seem to go better than many others when pushing into the wind.