Depends on what you're looking for and where you go and what's most important to you. Schedules? Upgrades? Route network? I mostly fly east coast and midwest, so NW works really well for me. On longer flights, I appreciate the F seat and the fact that NW has 16 of them. I have only visited one destination inside the Pac time zone -- LAS. It's skyteam's biggest hole on the west coast market (LAX-LAS not served by skyteam... alaska does it via a codeshare from AA so it doesn't count). It is reachable on DL via SLC, but that only makes sense if it's cheap enough.