I have the Crawlers on my rather bright Vox Custom 24 (maple going-thru neck, maple sides, rosewood fretboard), and a Mule neck on my SG. The Crawler neck and Mule neck are obviously related, and both have warm clean tones to die for, with enough clarity to cut thru. The Crawler might be a wee bit hotter and more compressed, but you have to understand the "more compressed" in the BKP context - it's still one of the more dynamic and open-sounding neck 'bucker I've ever played.
Can't comment on the Mule bridge obviously... The Crawler bridge is everything Tim and Telerocker said, and even more - vintage vibe with a bit more fatness and volume, chimey cleans and warm, singing lead tones, tight present lows, and works fine from pristine clean to bluesy crunch to fairly hi-gain.
The icing on the cake is the in-between position, which is kind of best of both worlds. As Tim said, playing with the switch and the volume(s) pots, you can pretty much cover all the bases - except possibly for the more extreme metal stuff (don't do metal so I can't really say).