| When you've already got a cool tone going as I'm sure you do with the EB-0/Bassman/Ampeg rig, I find that the Sansamp amp emulators cause a lot more harm to my tone than they do good. They're not just overdrives, they totally restructure your tone and alter it in many, many ways.
But there are tons, and tons of good overdrives that will work very well with your rig. A Fulltone Bass-Drive Mosfet would be good; it's quite versatile. The Homebrew Electronics Hematoma is also quite versatile with it's gain knob, going anywhere from light grit to full blown saturation. Those are just two of the many options that can give you great tone and versatility. | 
