If you have to have a CAL! get two. One for modifications.

Once that treble range is smoothed out 

It is the same as the Denon. I think somehow the manufacturing might have some minor differences as I seem to remember Tyll showing that it measures slightly better than the Denon.

I own both the CAL! And the srh840. The CAL! has a slightly more pleasant tonality,  but I think the Shures are much tighter, cleaner, and more detailed. I prefer the Shures by a wide margin, but they also cost more than twice the price.

So, it does seem that the CAL's should be considered for the leaderboard, as they seem to perform way above price.

Specs look pretty close! (Kotori 201) Fostex 40mm biocelullose driver, and very similar shape... $260 is kind of highish tho and seems it's only available in Nippon.

I have seen this fostex model being sold for 8-10k yen, always assumed that it was the original from fostex on which the denon and CAL were based.

...that some people have said the m50's should go on the leaderboard...

Really?
Here is just one of the few places that I thinkg people don't like it at all.
It has even "lost" to the XPT100/HM5 on the cheapo headphone extravaganza