I stumbled across this site: http://www.r3mix.net which has tons of details about encoders, etc.

They had a recommended encoding rate for LAME which I'm using under RH Linux 7.2. It's --r3mix -b 112. This does VBR encoding with 112 Byte as the minimum. It also applies a ton of other options that are listed on the above site. It takes quite a bit more horsepower than straight 320KB encoding but it really improves space usage to quality ratio.

I cannot tell the difference from the MP3 that is made and the CD on the same audio equipment. It's quite good. The file sizes are managable as well. I have at the moment 1285 songs from my collection on the Rio Car unit and have only used about 6GB of space. Wide variety of music. Green Day, Alanis Morrisette, Classical, Eny, Clannad, etc. Does sound qiute wonderful.

Now to get this thing installed in the car.

Do a search on r3mix and you will find a lot of post on this board. Word has it that the 3.91 version of LAME that was released this winter has a newer --alt preset -standard that is a little better. Basically, the r3mix guy hasn't been updating his stuff in awhile. Whoever did the --all preset-standard was more involved in 3.91 IIRC. Basically, I don't think that you will notice the difference, but you may want to look into it depending on what version of LAME you are running.

The one who developed the alt preset standard maintains a site at www.hydrogenaudio.org