I have a green and starwood, I generally use my points in MR as I earn them, because my fam lives in TN, so I use them instead of payin for the tickets provided the ticket cost is more than 350-400$, otherwise I just pay for it. I like green because I can transfer to southwest, but with starwood I can transfer to AA, who also makes non stop to BNA. Is there any reason to keep the green card over starwood?