I have about a dozen sets of headphones including some "high end" ones including Audeze LCD-4, Sennheiser HD800, and Sony MDR-Z1R.
The Sennheiser HD6XX get more use than any of my other headphones. They are not the "best" sounding, but they are very easy to listen to and are super comfortable (I often wear them to bed). I think they're hard to beat at their price point.
I have no experience with the headphone amp you mentioned, but the amp does make a big difference. The HD6XX will respond well if given good amplification. I use the Sony TA-ZH1ES.
The Sennheiser HD6XX get more use than any of my other headphones. They are not the "best" sounding, but they are very easy to listen to and are super comfortable (I often wear them to bed). I think they're hard to beat at their price point.
I have no experience with the headphone amp you mentioned, but the amp does make a big difference. The HD6XX will respond well if given good amplification. I use the Sony TA-ZH1ES.