I did H.O.W. last year - the shorter 25 mile route. I rode with a friend who had her 4 year old on a trail-a-bike. I thought it was a blast riding down Storrow Drive with no cars. And seeing some cool parts of the city I hadn't been in before, including the Forest Hills Cemetary. The seacost was nice too. The 1/4 mile of gravel was unpleasant because there was a steep little hill in it, but you could always walk that. I rode my touring/commuting bike with 26x1.3 tires. Rest stops were adequate and included mechanic support. There were volunteers at many of the confusing intersections so people didn't get lost. I enjoyed it.
Oil is good, grease is better.
2007 Peter Mooney w/S&S couplers/Terry Butterfly
1993 Bridgestone MB-3/Avocet O2 Air 40W
1980 Columbus Frame with 1970 Campy parts
1954 Raleigh 3-speed/Brooks B72