[Yardstick]

I posted in the AKG "K267 TIËSTO" - Discussion, Impressions & Review Thread about my headphones breaking a couple months ago.  AKG was really good about setting up the return, but sent a totally different headphone (K712) back as a replacement.  While the K712 is a nice headphone and there are some things I really like about it, it isn't the K267.  The K267 hit a lot of my wants in a headphone, but fell short in the durability department.  I'm not ready to roll the dice on another K267 at the current street prices.  I got a great deal when I got mine, but I wouldn't even pay that much to take the chance on them again.  
 
Here's what I wanted and liked very much about the K267: 
 
- Mostly flat, accurate frequency response through the spectrum as shown in measurements and heard in listening (I value objective measurements highly, but also look for subjective reviews from respected sources).
- Mini-XLR connections on both sides.  I mainly wanted replaceable cables, but came to appreciate the Mini-XLR and two-sided entry very much!  It is a very secure connection and now I'm into that connection type with a few cables.
- Ability to fold into a compact package.  Only folding flat doesn't quite cut it.  
- Closed back!  The primary reason I started looking for good over-ear, closed headphones was that I wanted to cut down outside noise in my office.  I don't want active noise cancelling, though.  It's not that loud.
 
Really, the only thing I didn't like about the K267 is that they broke!  Now that I have the K712, I realize the K267 is fairly hefty, too.  That's not necessarily a bad thing if heft = durability.
 
 
The K712 introduced me to open-back headphone sound.  It's good.  I like it at home in a relatively quiet environment when I'm not going to disturb anyone with sound leakage.  For me, it isn't a vast improvement or revelation in sound, though.  The sound is similar enough through most of the range (to me) but it does miss some of the sub-bass that the K267 could surprise me with.  What I really like about the K712 is:
 
- It's LIGHT!  'Are these things on?', light.  
- The adjustment mechanism is very cool and very comfortable.  Just put them on and they automatically adjust perfectly.  
- Still Mini-XLR, but only on one side.  That two-sided connection was convenient sometimes.
 
 
I would like a headphone that can be driven and sound good on a phone or Sansa Clip+ or Zip player for mobile/travel applications.  I have a Shiit Magni/Modi combo to drive the headphones at my desk at home, but the K712 can live there.  
 
I feel like I am starting my search all over.  I have re-read a lot of reviews that led me to the K267 in the first place.  A few new headphones have come out and a few others I considered have come down in price.  I'm curious if I'm missing anything, though.  Here's what I'm looking at so far:
 
K550 - Supposedly "built like a tank" and closed back. I'm guessing these are going to have some character that is closer to the K712 based on measurements.  No replaceable cable and the cable is very long for portable use.
 
PSB M4U 1 - Seems like these should fold up, but I can't find a good picture of them folded.  FR measurements seem a little jumpy in the mids, but flatter that some other headphones out there.  Build quality/durability??
 
NAD VISO HP50 - Seem to have replaceable cables, but not sure the connection type.  FR measurements look pretty good, but maybe a little rolled off toward the high end.  Build quality is supposed to be good.  The headband looks uncomfortably narrow and slightly odd to me.  
 
V-Moda M-100 - Thinking durability over absolute sound quality on this one.  Could they be modded to be more even than the measurements show?
 
What am I missing?
 
I apologize for this being so long, but I'm stuck and wanted to get this down somewhere for myself too.