You guys have to understand amps play a major role in this as well. Those data sheets, charts and graphs don't tell you the whole story.
On the B22 the HE-500s highs are a bit more top focused. The 5LE can handle that power a little better. The B22 is a pretty powerful amp. That's why it's really hard to compare these IMO.
Now on my balanced M^3 the 500s highs are not tilted, bright, hot, sharp or nothing. But the M^3 has a harder time driving the 5LEs compared to the 500s. The M^3 is a really laid back and warm amp - kind of tube-ish like (but not).
So the B22 is the only amp that I can compare these two on fairly IMO. Thus these are the results I came out with.
The 500s on the M^3 and the 5LEs on the B22 sound pretty much equal. It would be very hard to pick one out in a blind listing test.
I haven't tried the balanced CK²III with the 5LEs yet but the 500s are great on that amp as well.
I'll be doing some HE-6 and HE-5LE listing on the speaker amps later.