My work has a Marantz CDR300 that is the model below the one you mentioned and about $300 cheaper. We use it to record workshops and other events (we're a nonprofit organization so we do a lot of these types of things).
http://www.marantzpro.com/Products/CDR300.html
I like it mostly because of its portable nature (it's more rugged than other CD recorders and you can run it off of a battery pack) and its versatility (most CD recorders have only basic line-in, the CDR300 has XLR input in addition to RCA and 1/4"). In general it's well suited to live recording.
The CDR300 lacks the additional CD drive (?) and doesn't have all those other features like looping and pitch changing so I guess all I can say is that the Superscope's little brother is cool for recording.
Whether you buy one will depend on what you need. If you're just looking to transcribe solos and learns songs or play along, check out the Tascam's CD-GT1.

http://www.musiciansfriend.com/srs7/...base_id/101567
It has all of those slow-down and loop features without the recording. There have been some pretty postive review of it on the Review Zone.
http://www.tdpri.com/reviewpost/show...t=1&thecat=998
Heck, for the price of the Superscope you can get the CDR300 AND the CD GT1!
Anyway, there's some more options for you.
--James W