I keep the bulk of my miles with Alaska Airlines. They are partners with British, Northwest, Quantas, KLM, SAS, Continental, American, TWA, Canadian and Horizon.

I have never had a problem getting an award flight either on Alaska or any of its partners. Generally, I only use mileage for pleasure trips, so I plan them fairly far out. However, even when I do book first or business award flights, I sometimes have to keep calling back to find first or busines seats on some legs. I still think, however, that this is the best way to go (if you have enough mileage) because booking first or business ahead, you are almost always sure to get the seats you want--as opposed to trying certificates, good will or good luck. Of course, the gamblers, lover the thrill of anxiety waiting for the upgrade.

Whatever lifts your plane.