"You get what you want if you like metal."
I bought this pickup to replace the pickups of a Fender American Precision I bought from the first owner. I wanted to "personalize" the bass, like putting paint on the walls of a house you buy from someone else. I read a lot of good things about this pickup.
It comes in a cute box, it's made with care. It looks like a better product than the Fender stock pickups: even, fat sand-grinded poles (the poles of the stock pickup are slightly different in length, while the pickup-cover of the Fender pickup looks cheap).
I tried the pickups with a Peavey 150 w combo, and live with my Trace Elliot 300 w and 2 x 4 x 10". The sound is impressive. There is indeed extended frequency range. More "metallic" (high) and "boomy" (low). Less Precision-woody. Agressive, and hard to dose, IMO. Output is a misleading term in pickups, because 300 w is 300 w, you can't make more noice with another pickup. Read Bill Lawrence about it. Punchy? Yes, definitely. Full, in the meaning of warm? No. They are good for popping and slapping, with the tone-knob I could balance the lows and highs very well, so slapping and popping comes in equilibrium with finger-style.
I replaced the PU's with the stock-Fenders, and that's what I was looking for: full, warm, wooden tones. So I like the Fender stock PU's more than the SPB-3, because of the sound.
I think that when you look for agressive, metallic sounding pickup's, you can buy the SPB-3. They are cheap (compared to f.e. Rio Grande's "Muy Grande"-Precision PU's) and good looking.
Ease of Use:
Read above. It is hard to dose the sound.
What lack are the rubbers you put under the PU's. But you can cut them out of a piece of camping-bed.