Thanks for the feedback... That's too bad about TSA PreCheck. Honestly, I don't really understand why the airline has to "participate"... Why not just have a PreCheck ID that you show the TSA agent, regardless of what airline you're flying?

For buying at the airport, I assume you mean in advance? (Or are fares still pretty low on the day of travel?) If it's the former, then that's a bit extra time, plus the cost of parking. Weird that they'd charge extra for online booking... Aren't ticketing agents more expensive than computers?

I guess it's still worth considering if the price difference is significant (and BFS is available), but I'll probably still check Delta first.