Thanks TimC for your comments.
Regarding using CD-RW's - yes CD-R's are less expensive but I already have a bunch of CD-RW's and they provide flexability to re-use numerous times when recording mp3 audiobooks to listen to while driving.
Interestingly I paid less than a buck for the Sony CD-RWs (c/w with case) and the CD-Rs (good quality , eg Sony) cost about $0.40 (w/o case) - so (but not to make too big of issue of this) in theory since you can re-use the CD-RWs many times, these are actually the cheaper ones! <grin>
On the other hand - Is it possible that the CD-Rs would do a better job of recording...? (I often have a problem where I get some short audio glitches at the end of the mp3 tracks, which I suspect may be because I'm recording too fast...??? - or not...???)