No way man. I still have all three. Now thinking hard about the HE-400s. I just don't need all the bass I'm hearing they have.
What did you like about the 5LEs that you didn't like about the 500s?
For me on most of my headphone amp the 500s are a better choice. On my B22 and speaker amps the 5LEs are better. I love amps. So I have the new GS-X coming and trying to get a Dynahi built by someone.
There's really nothing I didn't like about the HE-500's - I thought that they had extremely smooth mids, nice bass, and very non-fatiguing. They were, to me, an enhanced HD650 with more detail and air. But they were very similar to my HD650's, so with my recent exploration and purchases of vintage receivers, speakers, and turntables, I was listening less to headphones and had a hard time justifying keeping both (HD650 and HE-500). I had built a Bottlehead Crack for the HD650's and have a small tube collection to go with it, so selling the HD650 would have meant selling the Crack and tubes - and having soldered, stained, and painted the Crack, I have some attachment to it. . .as well as the fact that it's more of a pain to sell multiple items versus just one.
As far as HE-500 vs HE-5LE, I thought the HE-5LE had more sizzle (more prominent treble and therefore detail at high frequencies), tighter bass, and were just more complementary (versus similar) to the HD650's - though the mids were admittedly not as velvety/smooth and they are less forgiving for suboptimal recordings.
If I didn't have the HD650's - or I didn't get into vintage electronics - I likely would have kept all three cans.
I can drive my 5LE's with a Hifiman EF5, Audio GD NFB-12, or via HP out or speaker taps from various vintage receivers. So sufficient power and having them sound close to their full potential isn't a problem.