I disagree with the $350 upgrade, even HNL-MSP.

At $.02 per mile, $350 is half-way to enough miles to redeem a RT award (albeit in coach) back to HNL from anywhere in the US.

Now, if NW gave you the F class bonus onto your miles, then it might be worth it. But since I don't believe that they do, grab the exit row on the DC-10 and sleep the night away. It might also be a different story if it were a daytime flight and there was some sort of "service" up in FC to speak of, but considering you're just going to sleep, bring a nice pillow, get the exit, and save $350 towards your next flight, upgrade, hotel stay, etc.

My $.02