Honestly, I think I'd have fun doing one just with a chill, scavenger hunt type mentality. Hang out and have a couple beers after sort of thing. I'm only 34 and a prospective parent, and still quite athletic and competitive (P/1/2 road), it's the traffic aggressiveness that has waned. But as you mentioned, you can 'ride your own race'! Too bad I never did one while RG was here in San Diego, I think Dave Scrod put on a few. I know some of those dudes from track.
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"Your beauty is an aeroplane;
so high, my heart cannot bear the strain." -A.C. Jobim, Triste