if it's only a tone down, I'd stick with ceramic. You're presumably not using a long scale length and fat strings on there. Course, it depends on your amp to a certain degree, too, and your style of playing. I use huge strings on a baritone tuned down to A-E-A-D-F#-B, and I hit them very hard, so a black dog gives just the right amount of push into a boosted 5150 to get utterly filthy. I never had a problem with a miracle man in a basswood ibanez (25.5" scale) in the same tuning with a set of 13s, although that was unboosted into the same amp.
Upshot: Unless you slam the front end of your amp particularly hard, I think you're better off with ceramic pickups.
Roo