One reason I've opted for AA instead of DL., LHR to RSW. The pricing was similar to AA but it came down to Schedules. I arrived in the early evening, with a decent layover 2 hours + at immigration with AA. DL flies more VA metal than DL metal which arrives earlier but I wanted a US carrier as SFAIK, there is no provision on an EU carrier for KTNs and there is no guarantee of a Preferred seat on a VA flight if you book thro' DL

The plane may change OK.

This may be a reason DL TATL are not flying to capacity. The choice was fly LHR-AMS-JFK-RSW or LHR-CDG-JfK-RSW when I can fly LHR-PHL-RSW and get a decent rental car at 6.15 p.m.instead of 11.39 p.m .? Just my take on it.