Well, what are your other domestic travel plans looking like? Do you have other flights you can burn the 500's on? I would think that HNL flights and longer transcons (LAX/SFO-IAD) would be the optimum situations to warrant burning a CR-1. However, if you don't have a use for the 500's OR you have some other flights which are tougher to clear UG's on then maybe save the CR-1's.

Bottom line is that I think only you can answer your question.