I've been a member of head-fi for almost a decade now. I love it. I buy and sell gear here. I've been burned by people raving about the latest and greatest headphones (D-66 eggos anyone?). I've also enjoyed more audio bliss by getting feedback from my friends on the forums.
There has always been a trend to my membership. I read through the posts to find out what the most intriguing headphones and amps are. I go through a two month period of buying and selling as much gear as I can. After that, I take a three year break before I go through the cycle again. I may have more disposable income during every cycle, but I still binge and sell before I quit :)
I have a few rules about my time on head-fi:
1) Avoid custom headphones. Low resale value. The UE10s made me very depressed, especially when they were outclassed by the universal SE530s that were half their price.
2) Wait until a headphone is at least 6 months old and the head-fi regulars have had a chance to check it out (the ones that can describe the difference in bass between a Ety4p and a Grado 225, people who remember the meta42 and the cmoy). The hype machine and new members can make even the worst headphones sound like gifts from heaven
3) Do not buy anything that gets updated every few months. I'm so glad I never bought a Xin amp when he was creating a new version every two weeks
4) Never buy new headphones or amps... get them used. It's like getting a discount for letting people burn in equipment! I love it!
5) Recognize the declining return on investment for high-end headphones. With rare exceptions, there are few expensive headphones that change the game. However, there may be a sonic signature I haven't tried before.
My last two major buys on this site have been the Ray Samuels Mustang amp and the Yuin PK1. I still have my trusty Shure SE530s.
Here's my question - if price is no object and rules 1-3 are important to me, what headphones should I buy next? I wish there was a single forum for all headphones like the good old days... the site is organized much better, but not for questions like this.