I'm looking at flights from SEA to SOF next September. I usually fly British Airways but the times flying to/from LHR-SOF are all wacky; same with Lufthansa. The most convenient times are offered by KLM and Air France, both "operated by" Delta. Both are the same price (booking Delta itself costs more).
So is there any good reason to book with KLM instead of Air France, or vice versa?
And how is Delta long-haul? I don't think I've ever flown Delta.