Vaughn- you are being a bit harsh about Mountain High's EDS unit and the technology required. Remember that this is intended for aviation use and not Grandma in the nursing home. Delivery in a constant environment is simple, whereas delivery on an altitude compensated system where the primary objective is oxygen conservation is more complex. Medical systems are designed to provide sufficient O2 under the "more is better" protocol. MH patented the altitude compensation part of the pulse delivery system, which is why they do not have any significant competition. I say "Good on Ya! and happily utilize the products. If it takes a special cannula, well that's OK by me. It is, after all, just my brain. And I abuse it pretty regularly with beer. Spending a bit extra for my flying safety is OK. It's one thing to be cheap with wing tape, but O2 delivery is somewhat more important to me.