I've had the good fortune to do three gigs in the last four days. One was crammed into a small local radio station, playing straight into an EV RE20, with no headphones, and no monitors (since there were 3 mics goin' in the studio). That gig doesn't count, although it did sound like my bass.
But on the other two gigs, I used just an RS II p/u for the first set. Then I set up the H-clamp and Beyer M88 starting with the second set.
To me the blended sound was better. More wood and air. A more convincing envelope and more dynamics to the shape of each pizz pluck and decay. So I stepped out a little more with my playing, rhythmically and harmonically. At least I think I did. I certainly enjoyed the sound more, thinking it was more natural. And I think that was reflected in my playing.
And in retrospect I kinda kicked myself for those nights when I was just too lazy to pack up the mic. With the H-clamp and a mic cable, I guess it takes me ... like 2 minutes to set it up. Not much extra fiddling around w/ knobs. Set the level on the mic channel and go.
In contrast, the solo'ed pickup sounds thicker and fuller perhaps, and quite good IMO, but not as open and natural.
I chuckled on the way in with the mic thinking "Sh%^, I paid $300 for the thing, I might as well use it."