do you know which bit rate the new unit can take? will it do vbr ? or is 192a better rate.
It supports all MP3 bit rates as far as I know, up to 320 and VBR. In theory VBR gives you the most "efficient" file by giving you a higher bit rate in complex parts, and lower bit rates when there maybe isn't so much going on. The average bit rate can therefore vary from track to track, but in reality I'm sure sounds just as good as 192kbps .
Maybe my hearing is not that great, but a while back I took a range of music styles on CD and created 64, 128, 196, 256, and 320 sample rates of each type. I then played them all through a variety of speakers, and honestly, for me the cut-off point was just 128kbps. After that I couldn't really appreciate any difference, so I stuck at 196kbps as a decent compromise on size vs quality. At the end of the day, 320 is going to be better than 192, but it's whether or not you can tell/appreciate the difference. I'm no audiophile though, but then again, no true audiophile would use a lossy compression anyway!
Let me know if you'd like me to actually test VBR to see if it plays.