First, I think KK will go for the glory; after all, it's got to be a major motivation for him. But looking just at the financial part of it, I think on balance he'll think it a good investment. While surely the Olympics is more chancy than Chicago, winning a big non-Oly race is no sure thing either. He could cramp, suffer injury, be out of the prize money. The attention he'd get in the run-up to the Olympics (cover of SI? T&F News?) would be invaluable to him in establishing a name beyond the narrow world of track nuts.