Nice thread. I've been thinking of getting a second hand TD-6 jobby at some stage, they seem really good.
Get one if you want a good drum module.
The actual sounds in it aren't too good, but to be honest, I haven't been impressed by any built-in sounds in any module. For the first few years I used it to play with, then using the midi out to record midi and playing through S2.0, and recently I've been using it with a trigger with my acoustic bass drum. There's one fucking kick ass metal kick sound in it others pretty much suck though