For overdrive, I like the Fulltone bass drive. The boosted midrange in some settings may make it feel like the low end is being cut, but as I said before, it is just it boosts the mids, so the drive cuts through nicely.
For fuzz, I use the Earthbound Audio Effects Supersollider. It's based on the Muff circuit, but just outperforms it in every way, bar price and availability. Hold the low end though the depth knob, which is hard to decribe, but awesome. It allows you to control mids, rather than the standard scoop from the muff circuit.
I also have an ODB-3. Pretty rubbish in all honesty, with very few usable tones, but it can get some ridiculously heavy distortions with some good use of the EQ section.