I've stuck with my trusty Audio-GD NFB-12 for almost 2 years. It's outlasted a Schiit Bifrost and Schiit Asgard. I like its sound and price such that I sold the Schiit stack and kept the NFB-12 for primary use. I currently am using Fostex T50-RP and I'm very happy with them for the minimal investment.
I am going to make a pretty big leap to $1000+ headphones and accompanying DAC / Amp over the course of the next few months, but I'm not sure which one I should purchase first, the headphones or DAC/amp. I'm looking at Sennheiser HD800, or Audez'e LCD-2 Rev. 2, or LCD-3. For DAC/Amps, I think I am going to go for another Audio-GD product. Likely the NFB 10.32.
I am thinking that I should buy the headphones first and use them with my NFB-12 until I can purchase a new DAC/amp. Would my NFB-12 drive the LCD-2 or LCD-3? Realistically I think I will get the Sennheiser HD800. Should the NFB-12 be a suitable match for the short period of time with the HD800? I feel like there would be a bigger benefit in diving into new headphones, instead of getting a new DAC/Amp and using the Fostex T50-RP for several weeks.
If it were me investing that kind of cash and I already had a DAC/Amp I am happy with I would not hesitate go invest in the latest and awesome LCD-3 headphones. The last pair from late 2012 that I tested were simply awe inspiring with their quickness and open feel. You may also want to look into a custom IEM if you can stand them because the sound can be quite good. They are of course way more portable than almost any high end headphone. Something like the JH 11 Pro or JH 10 x3 Pro may be right up your alley.