The standard corvette has the pickups placed as in Fender Jazz, for a classic bass sound. Ok... the final result is not that standard, since it is a Warwick after all.
The streamers have the pickups moved closer to the bridge. The thumb 5 has the pickups even closer.
So they pick the sound from the different part of the strings, they "hear" other harmonics. So the sound character is different. The result is a tighter sound, with more growl.
While I was writing these lines, it just crossed my mind something.
This is just a speculation....
When you play harmonics, as you go to the end of the string, the harmonics are closer and closer. So I think a pickup placed closer to the neck will bring more of one or another harmonic, while the pickup placed closer the bridge will "Hear" a more complex sound, since there are more harmonics in that point.
So the "Creamer"s sound is more complex than a standard Corvette.