I've been playing with mine for about a week. Overall, I'm satisfied considering what I paid, but I'm not blown away.
Impressions:
The battery life seems to be more than adequate, and frees up a lot of concern over charging every day, etc.
The screen is beautiful, but less than useful for picture viewing. When cycling through larger pictures, there is a considerable (5+ seconds) delay when cycling. I also have not found a zoom or pan function, which is unfortunate.
The unit gets plenty loud enough for me, contrary to what some users have said. I use it mainly with my E3cs, and only need to set it at about 15% power to have it playing loudly. On the other hand, I have to set it to max volume or thereabouts to use it successfully with my car via an auxiliary input.
As for sound quality, I have no complaints...provided the files are good quality. I originally started ripping my CDs at 132kbps ATRAC, but upon playing them on the device, discovered that some songs sounded terrible. I have since switched to 256kbps, and they seem adequate.
The interface took some getting used to, and I still don't love it. Although it might eventually become natural to operate the device, I have to admit that the Ipod is much easier to master.
The build quality is flawless, so far as I'm concerned. I really couldn't imagine the construction being any better. No complaints at all.
Also, the photo-downloading function works for me, and I have a Fujifilm s602 . The transfering is a bit slow, but the fact that the function even exists is quite impressive.
Finally, the remote is a real downer. I've been trying to rely on it exclusively to operate the device while driving, and find it to be intolerably slow, and confusing. There simply aren't enough buttons to work every function without menu-diving, and the screen isn't large enough to boot.
Overall, though...at $240 the capacity, sound quality, build quality and interesting design make it more than worth it.
Feel free to shoot me more specific questions.