Warwick RB5 passive. 
Markbass LMIII / Warwick BC40 
2x10 custom built oversize Aldred Amps cab. 
 
Second set of DRs I've used - same as the first, but heavier gauge. They fit just right. Had them on about 4 months now, have been playing regularly but only a couple of gigs. 
 
Took a few days to get the neck right for the tension of the strings, but now I've got sizzle, clarity, boldness - though not so much that I can't EQ the high end out for a less present sound. 
 
Now, I'm not great when it comes to Slap. I'm learning, but still can't articulate in the same way other good players can - so I asked a few of my more skilled friends to have a go; they didn't feel the strings prevented them from 'saying' what they wanted to 'say'.