Alaska - very good program due to its partners

check out the details on their site.

All our "orphan" miles flying DL/NW/CO are now dumped to AS.

Our main programs are AA and followed by UA - those miles are hoarded for long-haul premium cabins. I use Citi's Thankyou points and AS miles for domestic/Canada flights when I cannot find reasonable fares and we must go. Otherwise I pay to fly when fares are good. Case in point, I bought r/t FLL/DTW for $129 all-in NW flight. To fly to YYZ, NW is the cheapest, but still costs $260 all-in. The difference in fare x 2, is almost enough for the one-week rental car from National, pick up at Detroit. So we will fly into DTW for our Toronto trip in Sept.