In my opinion all P-basses should be passive...period.
If you are a P-bass player get the passive version.
With that being said I am not crazy about the SuperP passive, bidirectional rolloff. So I took it out in and put an old school pot-cap like a regular P-bass.
I'm a big P-bass fan, my two favorites are my 59 (La Bella flats) and 73 (rotosound swing bass round).
As for the SuperP...
ever since i switched back to a Pbass about 10 years ago I have spent thousands and thousands of dollars on any boutique 5 string bass with a P style pickup in it, only to sell it in three months because the B string was wobbly or it just didn't sound like a good Pbass. They all seemed to lack the lower mid grunt and sounded nasal.
My search is FINALLY over. This has a good B-string and a great P-bass tone. In addition it has a nicely contoured neck, unlike the traditional P-bass.
If you want a 5 string P-bass the Dingwall is the only one worth spending money on. It will not disappoint.