[Bazzman]

For me it was a pair of MB Quart QP90 phones from the early 90's that I found in a HiFi shop. My first real pair of serious headphones. The detail from them blew me away.
Sadly an amplifier fault put dc into the drivers and blew them.
Never found a pair since until I found some MB Quart QP400's from the USA.
Brought them as they looked the same and boy  am glad I did the detail from them is stunning.
Even though I have other phones (HD650's K701's) I keep going back to the Qp400's. If they had a bit more bass then my HD650's would be retired.

 

[krmathis]

The Stax SR-007BL
 
My first entry into higher end headphones, following a Grado SR80. I have gone through numerous headphones since I bought it more than 4 years ago, but besides the K1000 nothing have come even close in performance. Definitely a keeper.

 

[MuppetFace]

For me it's the Stax SR-003. They were my first pair of Stax and are still among my favorites.

 

[KarlAgathon]

Koss PortaPro. No matter what can I move on to, I always end up going back to them for some use here and there. They are just so fun!

 

[dspang]

+2 on the Ksc 75.  If I have these on I still have moments where I just stop and listen completetly dumbfounded that they were 15 dollars.

 

[kite7]

I resurrected my KSC75 recently by replacing the plug, still the best $20 headphones ever. The only headphone I bought twice was the SR225 before I decide to take a plunge for the RS1. Learned that wood cups aren't going to bring any prestige series grado close to the RS1

 

[Meyvn]

In terms of what sees the most use, the KSC35/Porta/Sporta family of drivers, without question.  Much as I like the KSC75, I really resent their discontinuation of the 35.  In terms of what I like the absolute best when I have the time/inclination, the K1000.  

 

[K-MONEY]

How comfortable are the K1000?
 
Quote:

The Stax SR-007BL
 
My first entry into higher end headphones, following a Grado SR80. I have gone through numerous headphones since I bought it more than 4 years ago, but besides the K1000 nothing have come even close in performance. Definitely a keeper.

 

[ljokerl]

 
Quote:

The KSC75. Haha

These. They never cease to amaze me and aren't really worth selling anyway (not that I could raise my hand to sell them).

 

[krmathis]

How comfortable are the K1000?

I find them really comfortable. Not quite up there with the O2, but not far behind either.
Some force are applied through the temple pads, but when I spread the pads almost all the way apart I can wear the K100 for 2-3 hours without any discomfort.

 

[Meyvn]

Quote:

How comfortable are the K1000?
 

 

They're quite comfy, in my experience.  It's very cool (literally) to not have something touching my ear at all.  I prefer them with the bigger head pads removed and the adjusters all the way in personally.  
 
Kai, have you tried removing the bigger pads?  I wore them the way you do until I discovered that "option."  Oh, and to top it off, I move the smaller pads to where the bigger pads were.  

 

[129207]

I gave my old Portapro's to my little sister but everytime I visit her I steal them for half an hour before I go to sleep.  

 

[kboe]

Grado SR-80s.  I kept these the longest.

 

[Uncle Erik]

The K-1000.  I've sold my other early headphones, but have had them around for nearly four years.  I find them very comfortable, too.
 
The only other pair I feel as committed to is the HD-800.

 

[kboe]

I too found the K1000s really comfortable.  I didn't think I would based on how they looked, but they sure do wear nice.