Dave
I have a TC M-One-XL..excellent unit,very quiet, highly recommended. I originally picked it up to use with synths/recording, but I've recently been messing around with it in the effects loop of my Mesa. I mostly use it for chorusing, delay, and tremolo effects. I really havent tried the reverbs on bass yet, but the sound is excellent on vocals,strings,guitar,etc, so I see no reason why they shouldnt sound great with bass too.
I also have a Midi-Verb, although thats also a nice unit, the TC blows it away. The only other reverb I can personally compare it to is an old Furman 2 channel spring unit,it has a nice drippy/boingyness to it,but thats of limited use.
Do check one out if you can,I think you'll be impressed,not only are the reverbs nice,but the chorusing is about the best I've heard.
Gary