Here's the deal with 9050's: they do have growl. They are not your father's round, woody tone flats. Whether they will work on any given bass depends entirely on the resonance of the body of the bass. I have tried them on everything: maple, ash, asian mahogany, alder. To my ears, they work best on a neutral alder body with a bolt on neck, rosewood fingerboard. A bass of these characteristics tends to have a slight dip in the natural resonance of the instrument @ 400 Hz, which gives clarity and definition to the 9050's. Maple overworks the growl; ash and mahogany have tonal signatures that do not seem to be compatible with the 9050's: ash, again to my ears, seems to draw the life out of them, and asian mahogany, having a different midrange resonance, makes them sound nasal to me.
Your mileage may vary. Rock on.
I use the 9050Ls on my MIM Ash/Rosewood J-Bass (CS60s) and Squier VM fretless Agathis/Ebonol (SD QP). They sound similar but markedly different. Both have a nice growl, the Ash/Rosewood J sounds sweet and focused and the VM J has more of a distinctive growl and sounds like it has less high frequency content. Both took a while to break in.