The guy at my LBS pretty much convinced me to pass on getting BTCs installed on my new Surly LHT, and encouraged me to just get a nice bike case instead (he showed me some $350 3 layer case).
They seem like a huge headache, as we spent about 10 minutes trying to find shops in our area that would do it, then he told me it may need to be repainted, that the frame tubes may be tapered so the BTCs may need to be placed in odd places/not be placeable at all, and that it could take up to 12 weeks to get the bike back.
Finally he made the point that the BTCs aren't going to make my bike more compact than the diameter of my tires.
I have never traveled with a bicycle, will the few extra inches afforded me by the BTCs (maybe many extra inches?) do something for me when it comes to flying?
We may also at some point store our bikes in an airport locker in Europe, will they be able to fit without BTCs? Would they be able to fit even WITH BTCs? (I admit I have never looked at an airport locker)
I have not yet bought the case, and I realize that even if I got BTCs I would need to also buy a case on top of their cost. However I am still open to the idea of getting them if somebody has some persuasive reasons.