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
For DMs, the opportunity cost is a bit over 4000 miles per SWU, at terms of trade of 6 SWUs or 25,000 bonus redeemable miles.
A big difference is that SWU upgrades can happen at the gate, while miles upgrades officially must be confirmed before e day of travel, but YMMV. In fact SWU upgrades if coded right have very high priority at the gate.