I haven't actually redeemed any miles.and I have nearly 300k so need to start. Just playing around with it, it seemed to me that the 10k redemptions are not worth it bc, as mentioned, the fares are cheap. The 20-25k mark might be where it's worth it since it seems to stay in that range for fares that can be several hundred dollars before the flight just shows unavailable.

It's also been mentioned on the forum that Caribbean destinations are good value even when you factor in the fees and taxes but I haven't played with that at all using sample bookings.
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