Really? The Amazon product description says: "it's a tech-savvy player that spins your MP3- and JPEG-encoded recordable CDs" which makes it sound like it only plays mp3 from cd-r. Also, when you say it's not an audiophile-quality source, what does that mean exactly? I'm expecting it's not as good as a Marantz or something, but will it be better than most pcdps?
It can read DVD-R and CD-R with MP3, JPEG, AVI, MPEGS, etc. I bought one a long time ago and even my version has no problem with them. Unless the newer 642's are different, it should pose no problems. This thing is almost like a CD-ROM drive.
It should sound fine. Nevermind my earlier comment. If you're going to be playing MP3's then you shouldn't expect audiophile level sound anyway.