I'm not a business traveller, but I do make frequent travels to London over several years. I live in Cincinnati so I also know Delta very well. I would take BA over Delta in a heartbeat! The service is SO much better, the seats more comfortable, the offerings more plentiful, the food is better...we always check BA first for flights home. If it is within $100-$200 of the price of Delta, we will spend more for it. And I'm pretty well known for being cheap with the money--but for the difference in comfort, it is well worth it!