Join Date: Jan 2006
Location: Atlanta but Washington DC will always be home.
Programs: Marriott LTP, Hilton Diamond, Accor Gold, Hyatt Explorist,, Delta Plat,
Posts: 2,074
I wouldn't risk it. You'll come into E on Wow, and almost all of SOuthwest's last flights are from A or B. You'll clear customs at E, have to walk to A to check bags and clear security (Southwest only does domestic check-in at that hour at the A-B entrance) and then walk to your gates.
This all is assuming that Wow is on time (it often isn't) and that you don't happen to arrive at the same time as BA or Condor. It doesn't happen often, but when it does Immigration is hosed. Hosed.
I'd take the real economy+ and decent connection even if it is $400. If $$$ make the decision, do BWI and stay at the Red Roof Inn +. It's clean and comfortable, newly renovated - wouldn't stay there for a week but its absolutely fine for 1 night. Rates from $50-80.