Several comments. First, I tried Diamox one time when going to altitude. It did seem to help with the sleep disturbance but not with any exercise tolerance. Not surprising given the mechanism of action. Indication for this medicine is prevention of altitude sickness. I can tell you more about this if you want to contact me directly. If you are not prone to altitude sickness, I do not recommend it. Tends to be dehydrating which is not helpful during a race. By the way, the reason it is banned is because it is used to mask performance enhancing drugs.
As far as Ginko, the studies have been inconsistant. Unlike Diamox which has been well studied and has clearly documented benefit for preventing altitude sickness.