It really depends on what you plan on using your CO miles for. If international upgrades is a priority for you, then yes CO may be a poor choice. First Class domestic upgrades are still the same value. I put my MR points to airlines which participate in the Hilton Hhonors reward exchange where I can then get two hilton points for every mile. So, in this example, your 80,000 MR points could become 100,000 CO miles (including the current 25% promo). These could then be transferred to your Hilton account for 200,000 hilton points. These are worth two, six night stay awards in hawaii (assuming you are a Hilton VIP). These stays at a hawaii resort would easily cost you $4000 or more (calculated at $330/night).

Thus, you could theoretically redeem your 80K membership reward points at a value 5 cents each! (4000 /80,000 = .05 )