It doesn't solve the problems described in this thread. I haven't done a side-by-side comparison between the two, but I'd put it about on par with my Total Bithead in terms of (lack of) soundstage and coolness of sound. I think the upgraded power supply fills in the sound a bit with the headphones I have at home now (just the HD600s), but it isn't a big change like it is with speakers.
Basically, as a headphone amp the Nuforce Icon sounds quite good until you've listened to something better. I listen to the Bithead all the time at work, so to be fair, the Icon should be perfectly usable as a headphone amp, and will sound pretty darn good as long as you aren't expecting the world from it.
As for the DAC, it's good, but I can't give a fair description without doing any direct comparisons to other DACs. The only time I've used it as a DAC with the line-out to another amp was quite a while ago (6+ months) when I was borrowing a DIY tube amp from jopagi (not one he'd built), and I can't recall what that amp was. I was unimpressed overall with the combo, but it may have been the amp or the DAC, and I didn't have any other equipment to compare against at the time.
Right now I don't have any other good DACs to do a side-by-side comparison to: my Paradisea 3 is very sadly being sent back to fix a clipping problem (
http://www.head-fi.org/forums/f7/par...ipping-435092/), and the Pico DAC+Amp I ordered on Friday won't be here until sometime later this week (fingers crossed!). I'll do a comparison between the Icon the Pico once it arrives, but from my experience with the Icon and everything I've read about the Pico, it won't be a contest...