I know this thread is old, but I wanted to share my experience with the AER forks.

I'm only a C rider, keep that in mind when reading. At first, the AER for was the best fork I'd ever ridden. Which to me meant that it liked to stay up in the stroke, it could absorb square edges extremely well, and it was pretty smooth over baby heads.

However, I found myself always playing with the air pressure. It went like this : right after an oil and seal change, I'd run 128 PSI and the fork would be great. Then, after 6-8 hours, it would start diving too much and I'd up the pressure and more compression damping. Then it would start bottoming on square edges and I'd add more pressure and compression damping. By the time I had 20 hours on the fork oil I had 145 PSI in it and it behaved like a completely different fork.

I'd change the oil and seals and I'd be back to 128 PSI and a fabulous fork.

I eventually tired of dealing with a fork whos characteristics were always changing and I spent big bucks on Ohlins forks. The Ohlins forks are about as good (to me) as the AER forks right after an oil change, but they don't start degrading for at least 30 hours.

I don't think the air spring is the problem. I think that cramming compression and rebound into a single leg is just too hard on the fork oil. Unfortunately the new XPLOR forks do the same thing. I'm not running them, but my reliable source tells me that the XPLOR forks also eat oil very fast and need super frequent oil changes to reliably work well.