Originally Posted by glye

Right, given that customs situation it's understandable. And if you can't find any domestic bike parts company that imports these things, you're limited indeed. Too bad.

Brake upgrade: I see no need. The original works very well. Brake power depends on both disk size and wheel size. With the tiny 355-size Birdy wheels and relatively big 160 mm rotors, you get good braking. It corresponds to something like a 260 mm disk on a 29er wheel, but they are often happy with "only" 200 mm.

RT86 with opposite rotation: Yes, potential problem. Should not be run backwards, and may not fit when flipped. Try before you buy