My new bike came with Aerothan tubes installed in Schwalbe tires, and they work great. They are, as advertised, extremely light with excellent rolling resistance. They're also very compact (roughly half the size of a regular butyl tube when folded), so they fit neatly and easily in either a smaller saddle bag or a jersey pocket. They're not puncture proof, but they do at least as well as butyl tubes in resisting punctures.
When I got my first flat (rear tire), I put in a butyl tube, and noticed an immediate difference. It was harder to pedal, harder to accelerate quickly, and harder to hold speed on the road. After I got home, I ordered up some Aerothan tubes, and replaced the butyl tube in the rear tire. I was amazed at the difference the Aerothan tube made.
Are they worth the substantial price difference? Maybe not for a commuter or casual recreational rider, but for performance riding, they can't be beat. And contrary to reports from some reviewers, they CAN be patched, although you must use Schwalbe's glueless patch kit, which is readily available through WBW/BTD. Yes, they're expensive, but they make a noticeable difference on the road. I'm sticking with the Aerothans. The better ride quality is worth it to me.
I bought a pair of these for a 24hr time trial. Used with 700x25 Conti GP5000s the ride was noticeably cushier and seemed to have less rolling resistance.
Won the race and set a course record. Guess they worked
I use the Presta version on my mountain bike and the Schrader valve version on my klunker. Goathead thorns are a problem here no matter what you run, so I canï¿½t fault them for picking up a flat from them.