How much do you want to spend on a DAP? I am partial to the old iRiver H120 or H140. These can be modified to accept 80 Gb or 120 GB hard drives respectively or up to 64/128 Gb CF cards at a much higher cost.

The iRiver H140 (40GB) can be had for around £80 - £100 on eBay. Whilst it does have an inbuilt FM radio, there is no obligation to use it .

I bought one last year because I can use it to store all my music in OGG format, and because it has an optical line out which I can feed into my Cambridge DacMagic, which connects to my Solo UL/Senn HD250 LII/Senn 650s.

However the inbuilt DAC & amp on the IRiver is very good as it is, and it sounds excellent with my Koss Porta-Pros with no additional amping, although I must admit I have been toying lately with the possibility of getting a Voyager so I could use it direct with the HD250s instead.

On the move, I currently tend use my Creative Zen 30GB with the Porta-Pros, as it is smaller, lighter and has a rather more user-friendly interface.

I agree with hotmog - the H1x0's internal headamp doesn't have enough juice for HD250's; it has only a 5v battery after all. Grado SR60/80 aren't bad though. With ear canal phones the noise floor is clearly audible.