I posted some more detailed thoughts in a couple relatively recent threads, and so did one or two others.
Pine green was a great compressor for bass.
Candy apple fuzz was good considering how rediculous it got. Maybe not 100% low end, but seriously beefy and enough fun that you ignore the settings that lost some bottom.
Model H. I'm an idiot for selling it. I've said before that it didn't keep ALL your lows, but the roll off wasnt terrible at the bottom of the tone knob. Higher on the tone knob there were less lows, but it REALLY brought out the mids in a nice cutting kinda way if thats ever our thing on bass. also, lower gains were pretty good with keeping lows, its the cranked gain and higher tone settings that did it. If you're just a bassist, something in this vein with more bottom would be sweet, but it would loose some of its unique voice on guitar (I had it in a parallell loop with a BBBOD for a while... Sounded unbelievable)
I'd love to try a Little green wonder too... so many bass moded tube screamers out there that people love, I should really try an LGW (and a phaser and autowah
) eventually... but I think that won't be until I look for a model H again one day...