Thank you all for your input. Seems its true that I would not have had expired miles but at this rate, might as well use the miles anyway. No matter how it goes, 15 hours is not easy. We ended up with seats in the middle section of the configuration. Though its 4 months away, I will let you all know how it goes from a balanced perspective. As mentioned, we typically take CX to HKG and beyond. Just had questions with regard to how CO (our domestic carrier) serves that route.