Hell you guys don't know what wind is! You wanna come shoot in little Ol' New Zealand! Our mountains stick way up out of a our skinny little country and catch every darn bit of wind in the southern hemisphere, or that's what it seems like when we're up there trying to shoot long range!
Anyway, you're quite right, minimizing wind drift is all that matters so long as you have a good accurate rangefinder and system for accounting for air density changes etc, and you shouldn't be shooting at big game at long range if you haven't.
Bryan's G7 BC's are always my starting point for any new bullet when I start field testing, and they are always pretty close to what I get from drop testing. There are small variances at times, but generally due to something unaccounted for in my rifle/scope setup, or some vertical from the field conditions of the time. Yes, you need to verify all BC's in all rifles, but Bryan's G7's are the only ones that have come close enough to get me on target from the get-go.
Actually, I have to add that since I've been trying some of Dan's Cutting Edge bullets, their listed BC's have been bloody close as well. Especially when you consider Dan lists G1's that are more velocity dependent, and we're pushing them significant faster than the speed he calculated his G1's off.
We've been testing some new acoustic electronic target trickery on my 1000 yard range recently that the NZ NRA and F-Class boys are hoping to install at their ranges throughout the country. This stuff uses a 5 microphone setup and should be able to give extremely accurate remaining velocities and therefore BC's which will be very useful each time a new bullet comes out.
Yes wind drift is all that matters, but the best combination of high BC and velocity is what gives you the least wind drift, and accurate BC comparisons are always going to be your starting point when choosing a bullet for long range.
That's my 2 cents anyway!