But it’s not quite as simple as that. We found good deals from Aerox and SkyOx, too, but features and accessories vary. Read our fine print for more.

By Joseph E. (Jeb) Burnside

It’s no secret serious use of a personal airplane requires climbing far above pattern and practice altitudes where the air is thinner and true airspeeds peak. That, more than anything else, may explain the veritable explosion in complete, state-of-the-art portable oxygen systems and the accessories that go with them. If your airplane doesn’t have built-in oxygen, and the time and money to add it isn’t in the cards, you’re a prime candidate for a portable system. Total cost for a two-user system? Under $500. But if you usually carry more people or need a few bells and whistles, things start getting complicated: The choices available from some vendors can be…