matrix for looping units?

[Shayne Cafferata <scafferata@dlcwest.com>]

 It's so cool to see a bunch of my faves in your cd players - Material,
Michael Brook, Eno, Fripp/Crafty Guitarists, Tom Waits, Steve
Hackett(Spectral Mornings and Defector are among my all time favorites -
what is he up to lately?), Pinback, Pat Metheny, Bill Frisell...
Forgive me if I sound surprised, but I live in cowtown on the lonely
plains of Saskatchewan, and I'm so used to having *noone* who shares my
musical tastes.

Is there a matrix(like in Keyboard or EM) that exists anywhere that
compares looping machines? I need some suggestions as a base to start
looking. I'm probably limited to around the $200-300 range right now and
I'll probably look for something older and used as opposed to new.

Thanks,
           Shayne