I think there are several factors people forget when they say BF is cheaper. 1) are they including cost for LBS to disassemble/reassemble bikes (or are they doing this themselves). 2) cost and time at both ends to go to LBS to drop off/pick up their bike. When I travel with my bike, 1st thing I check is what the baggage fee is for all the airlines that go to my destination. I then include that with the ticket cost to see which airline is cheapest. I also dissemble/reassemble my own bike. At destination, I take free hotel shuttle, reassemble bike at hotel, stay a night (usually both the first and last), and have hotel store my hard case box until I return. Did this last year with 2 bikes (mine and wife's) to Paris/Charles de Gaulle Airport and it only cost $300 total for bikes. Over 3 week tour, that works out to $15/day for both bikes; which we look at as a bargain compared to car rental, or trains, or renting a bike.

I agree, BF gets better rates for shipping than most people can on their own (possible exception being if you can ship using your employees discount). If you don't want to be hassled with assembly/disassembly than its probably a good way to go. But I will bet that BF can not be less expensive than you personally doing all the work.