[Lurkumaural]

Update: I am much closer to buying.  Not at all closer to having made a decision.
 
Considering that I do not want one of these headphones more than the others, I will probably allow impulse to guide the purchase.  Maybe I pick a day and a time and whatever I am feeling at the moment will be the one I order.
 
For closed: SRH940, D5000, Pro 900
For open: Q701, AD900
 
(See how I added one since last time?)
 
I gave a lot of thought to the many flavors of Sennheiser open cans.  I think what I came up with is that they will probably be one of the next purchases after this one.  That's gonna be another pleading thread because I don't know which one I want.  I read the Headfonia article about the HD 55# comparisons, but I'm leaning toward HD 650 primarily because it's been said here that it will scale better than even the HD 600.  I think a 650 is what I heard for five minutes at the last meet on Doc B's Crack and thought it was something I could sit and listen to all day.  This was next to a K1000, which I gave up on because I probably don't know how to properly put them on and kept moving the speaker trying to find a sweet spot.  I heard the 600 that day, and didn't think as much of it, though the source probably factors in (Doc had a gorgeous live jazz recording on a beautifully restored tape reel).  It also occured to me that while I liked the 650, I really haven't done much open can listening and wanted to do some more before calling these the ones.  And this is the reason it's not on my list this time around.  Also there are the 701 and AD900 enthusiasts on here whose posts make me really want to give these an extended listen i.e. a few weeks post burn-in.
 
Okay, after typing this out, it looks like I should get something open this week. 
 
Of course, this may change later.  Every time I see a picture of the D5000, for example, it turns into image searches and online shopping.
 
side note: The Q460 was on the list very early on, and I said I wanted to give them a listen and have the three-button remote too.  They're off the list.  Especially considering price, I'm probably gonna go with one of the PX models with remote.  I haven't heard a PX before, but I remember when I was researching the KSC75 prior to purchase that the PX100 was mentioned very favorably as a bang for the buck can of almost the KSC caliber.  I'm rambling.

 

[Graphicism]

If you're not ready for a top-of-the-line (and by that I don't mean flagship) Sennheiser or Beyerdynamic then I would save your money and buy something like; Audio-Technica M50 or even cheaper the JVC RX700, which is basically a Denon D2000 in an all plastic body.
 
Q/K701 needs a ridiculous amp to sound good, people will argue but I've heard a few and thought they were hollow, yet long-term owners speak of correct amp matching.
 
AD900 is like a poor mans DT880, in fact the AD2000 would be a closer sibling to the Beyer.
 
SRH940 is probably the best you have listed for a good all-rounder, this is based off listening to previous models of the Shures.
 
D5000 is a fancier version of the D2000 which is a fancier version of the $23 JVC RX700, you're paying for looks.
 
Pro900 is excellent for electronica given that you have a decent solid-state, it falls a bit flat with other genres as I find it somewhat metallic sounding.

 

[keanex]

Whatever you do avoid ebay. The Ad900, for instance, are $220 according to you on eBay. They're new on Amazon for $215 from a trusted seller.

 

[Lurkumaural]

@Graphicism: I hear you about the TOTL.  It's one of the reasons I was flirting with price ranges higher than I currently own.
 
For sure I would use the 701 as an excuse to scale up, probably a couple of times over the life of the cans.  It looks like many K701 owners keep a few amps that are capable of driving them.
 
Argh.  If I end up hearing a Beyer and buying one before an open A-T, I will be back here to blame you.  I am right this minute searching for brick and mortar Beyer retailers in SF.  With the AD900 specifically I was going for bang-for-buck; it would be funny if I ended up with buck-for-bang.
 
I'm actually thinking the SRH940 is slipping down the list.  Aside from the FOTM discourse these cans have gotten, I think I am just less excited about these headphones than I was pre-launch.  I mean, they seem worthy for sure, but because of my indecisiveness I was hoping these would call to me more.
 
I was targeting the D5000 precisely because I've read about sonic refinement over the D2000.  If I went for the D2000, it would be because I want to get Lawton cups some time later, which from what I understand would put them past the stock D5000.  And the looks are quite important with this product line!
 
 
@keanex: I appreciate the nod to Amazon.  I see that the Amazon seller is Vann's, who are authorized A-T sellers.  On eBay, the seller would be Beach Camera, also authorized.  In New Jersey, no less.