I have the 350 model and I think it's worth the $130 it costs now. I get 4+ hours of music on 1 CD, and that's on good (320kbps) quality. I could probably squeeze 5-10 in 256kbps, 192kbps, and 128kbps. However, it supports VBR (variable bitrate) and that saves a ton of space and lets me squeeze even more music at good quality on to one CD.
The sound quality is fine with me. The line out sucks, though, but unless you plan on using it I wouldn't even consider it. The menu is
very deep. It allows you to fiddle with a ton of things.
The equalizer is awesome. It lets you corner the frequency amplified, from 50, 100, and 200Hz and below for bass and 2, 5, and 7kHz and above for treble at 12 different levels of amplification each. Or you can just use the pre-sets, Rock, Jazz, Classic, Ultra Bass, and Normal.
It brings two flat batteries that last about 8 hours (add 2 AA to the external pack and you're set for a week)
The new firmware upgrade even has the snake game found on many cell phones. Need I say more? Yes, because I can. It has new tweaks that lets you save even more battery power.
I've never used the imp-400 but I did some searches and found no reason to leave my imp-350.
At the time of my search for the best PCDMP3P a few months back the imp-350 was
easily the best I found. CD, MP3 @ many bitrates including VBR, WMA, upgradeable formats through firmware upgrades, and FM radio (because nobody can live without Howard Stern in the morning
). The only thing that came close was a RioVolt SP250 which was twice as thick (and cost $150, $50 less than what the imp-350 was then)
IGN review of the SlimX imp-350
IGN review of the SlimX imp-400
"After spending a day with the SlimX 2 -- it's not officially called that, but that's what I'll use for convenience's sake -- I can say with surety that this is the new reigning king of MP3 CD players."
you can also check out
www.epinions.com for user reviews. A word of caution: amateurs may say it's the greatest product ever without even trying a second option.
I'll stop here because I don't know if I'm tying it all together.
Good luck