Rode my first 600k this past weekend, and it was fantastic. Much like the 400k I described a few posts back, I had good company, stayed fueled and hydrated, and the weather was cooperative. We took a ~4 hr sleep break at the 410k mark and hit the hotel breakfast before heading back out for the last 190k. Total time was 35hr40min. I still had some occasional hot-spot issues, as well as a little hand pain/numbness, but they were all manageable. I will probably move my cleats back another mm and use firmer material to fill the low spots in the cleat mounting area.
PBP, here I come!