I chose the Comet, I might swing to the CV-340 if it's performance is satisfactory and shows improvmnet over the 240 and M 4-0-4 though.
Advantages of the comet:
-Higher speeds, they allow overcutting on routes, which won't turn them into battle fields as quickly
-Decent fuel burn.
-Good enough range that you can operate till you're near max and still make a good profit.
Downside:
Could've used more seats.