Rusty Box really catches that Shellac and Jesus Lizard sound. I've read that the rusty box is basically the pedal version of the traynor ts50b (Bob Weston of Shellac's amp).
They're out of stock now but are supposed to be back in late june. You could probably find one used though.
That said, I've played with a VT deluxe quite extensively and love most of the sounds I can get out of that pedal. You can find a ridiculous amount of info about the VT bass around here, but based off what you want I would recommend spending your 200+ dollars on another pedal. It does sound amazing to run the right overdrive, distortion or fuzz into that mini SVT though!
http://tronographic.com/
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