No, there is nothing wrong with my HE-500. There is a time, though, when you're familiar with something (like me and my HE-500), that you notice its faults to a greater degree than is fair. So, when I'm listening to classical and acoustic jazz, my HE-500 is just the ticket. At this time, though, when I listen to rock I want the drums to hit harder than they do through the HE-500. That an improvement, especially for $1000 or less, is going to be hard to find is the reason I started searching for ideas here rather than starting with retailers and my credit card.
What ever I decide to try, the HE-500 stay.
Let's assume Liu and I are exactly the same in our tastes: perhaps then the HE-6 would be the perfect solution. I may save some more money and try to find a pair in good condition to try. It is entirely possible that the HE-6 will be too bright for me (I am sensitive to hot treble, but not overly so). If the HE-6 turns out to be too bright, I'm sure there will be another Head-fi-er out there that wants them. With your two posts I see the big challenge for the HE-6 to win me over is the treble being too bright/ forward, especially since I plan to use them for rock recordings.
Thanks to everyone for their ideas. Any comments about Mr Speakers?