Music Man StingRay 4 Piezo FL Reviews 
4 / 5 based on 1 reviewsKinda Olde Skoole. Playing songs mainly 50 - 75 yrs old. More recent stuff is over 20 yrs old. Small ensemble, small rooms, backing Ms Diva and her big voice.
Used from Bass NW. Cost a bit more thanthe average used SR4, but the piezo option is almost $300 on a new bass.
I have other piezo basses, so there were no huge surprises here. I've wanted a piezo MM FL for a long time, altho ideally I was looking for a Bongo HH+piezo.
Fanstastic voice, intuitive controls, great neck. Swamp ash body [my fave].
I wish it also had a neck PU. EBMM doesn't ofter dual mag PU's plus piezo except on the Bongo.
EBMM. Nuf said.
I know that metal bridged piezo sytems [as opposed to wooden 'acoustic' type] can be finicky, so I'm trusting to EBMM to select only those components that won't smudge their reputation. So far so good. It's been no trouble to me. I don't know how much use the previous owner gave it [looks kinda new for 5yrs old ... ].
The piezo does nothing super astounding. It does make a very musical bass even more musical. The piezo can definitely hold its own, playing with the MM PU completely shut down. Some piezos are meant only as mix-in effects, but this one has "whole" tone. 
Adding the piezo option to a new MM is not going to be "the best $300 upgrade I ever made". But it's a distincly more musical sound, very suitable for the FL. If it were only half that price, I'd consider any buyer of a FL Ray to be mentally deficient to skip ordering it. At it's current price, I'm not sure every buyer would feel they got there $$'s worth. 
A bass like mine is about $1800 brand new, which IS competitive for what you get and for what you'll hear when you play it. It's just that you can bring home a very similar bass for $300 less [same ax minus piezo] and many buyers would be just as happy to do it that way.
Also, money aside, opting for the piezo means you can't have a neck PU. The neck PU is a much more huge personality change for a Ray [or Sterling] compared to the piezo. So, opting for the piezo means valuing a more subtle difference over a more in-you-face total make-over. 
With the Bongo, you're not forced into that either-or decision. That's why I was really hoping to bag a used Bongo. OTOH, in the used market, the piezo feature seems to hold only about $100 value over a regular Ray. They are VERY scarce, but for $100 difference, it's a no-brainer if you happen to luck onto one while shopping for a FL Ray [or Sterling].
Golem rated this unit 

 on 
2007-11-28.