The HE-5LE was to me, better than the HE-500, if the HE-5LE was adorning the Moon cable vs the HE-500's and it's stock one.
So it wasn't just a preference thing at that point, favoring speed over strength, but the silver cable adds the strength to the HE-5LE's agility.
Despite my saying that I was content with 5LE's and didn't really feel the need to check out the HD-500's even if I got a good deal. . .
Curiousity got the better of me and I picked up a pair of used HE-500's from another Head-Fi'er - they arrived yesterday. They came with the original Canare thick cable, but I have a variety of cables I can use:
* Original balanced 5LE cable
* Original SE 5LE cable
* Silver (or SPC, not really sure) SE cable that Hifiman sent to me for just shipping charge - looks a lot like what was shipping with HE-500's once they moved away from the Canare
* Silver Ray cable from Chris
Anyway, I agree with the comments earlier that the HE-500 isn't so much an upgrade as a sidegrade at this point. Granted, I only have 4-6hrs of head time and they only had 50hrs of head time from previous owner, so who knows, maybe they're not fully burned-in/settled.
I'm using speaker tap outs of my vintage Yamaha CR-220 receiver (15wpc) and the original 5LE balanced cable, which I know isn't the best quality, but at this moment it's the only balanced cable I have.
I agree that they're more polite sounding than 5LE's. The mids are smoother/more liquid and more prominent (5LE mids are a bit thin by comparison), but I find the bass a little looser and less impactful, and the highs seem a tad rolled off (or level is lower). Initial impressions are that they're noticably less detailed than 5LE at least at higher frequencies (especially notable with brushwork on some jazz SACDs), but I haven't listened for detail at other frequencies. Haven't listened specifically for soundstage either. Just first level impressions
To my ears, the 5LE's have more PRaT and are more distinctive in their sound signature versus my other cans like HD650. For that reason alone, my first instinct is to keep the 5LE's for sure. The HE-500's would probably be overall less fatiguing over longer listening lessions - they're very smooth. I find them to be similar in sound signature to HD650's, but not ready to comment on how they compare to each other (HE-500 vs HD650) in any level of detail. What I think will be the bigger question is whether it makes sense to keep both HE-500 and HD650 or whether they're too similar to justify having both.
The last piece that will allow me to do more direct comparisons is a DHC nucleotide balanced cable that will arrive today or Monday.
Overall, I'm happy with both the 5LE and HE-500. Since I bought both used, the price premium for HE-500 was $125, which isn't bad.
Will post more thoughts as I do more listening.