Hornady with Doplar radar. Most technologically advanced way of measuring BC. I trust Litz's numbers as well but Hornady has an edge on him with their radar capabilities.
I don't understand the point behind this survey though? I agree with gohring3006, the "I'm better than you" stuff is getting old. Everyone needs to do their own thing and stop worrying about how everyone feels about them. I agree Litz does some great testing to verify or prove how some bullets perform. But that doesn't make AB any better than Hornady or Sierra, who's BCs have always been spot on for me.
I don't see Nightforce or Bartlein commenting on here asking who makes the best scope or barrels. Leave it to the customer base to form their own opinions and don't ask them who they trust or who is the best. Ask them how they feel about Applied Ballistics numbers and how they can improve or whatever. Don't make it a Chevy vs. Ford argument, because that never ends well and is unnecessary. Just how I feel about it.