A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
AS has lots of bilateral partners, so you might want to check whether CZ is one of them if you can use their miles.
Otherwise, the fact that DL miles don't currently expire would get the win.