DL, NW, or CO? Which Should I Go With?
I normally fly AA or UA, but I have a trip on DL and a trip on NW coming up, so I figure I might as well pick up some miles on them while I'm at it. I probably won't fly a combined 25K this year so I'm not going for elite, just a possible award ticket in the future. Which would you recommend I join? Thanks a lot.