I bought this microphone to be passive quiet side "stack" and installation. I did it installed by my dealer on my Tanglewood TW15-H any mass return home, the sound was "good" (see very good) but the low E string did not give anything (we hear him ). The leaflet explains the need to try other positions, what I did ... good groin 15 times (I even had to order adhesives BAGGS LR) before finding a site with a proper balance between the strings!
I think it must be related to the type of barrier used in the table that this sensor does not immediately compatible with all guitars.
Right now the sound is there and the balance between the strings is not bad (not perfect when we check the levels on a sequencer but direct listening is good).
And its so: incredibly natural! I plug in my LR BAGGS Para Acoustic DI (oh yes it is a very good preamp output for the passive version has a very low level!) And my recordings sound more lifelike (I made comparisons).
In short, a very good sensor for those who want a natural acoustic sound that really makes his guitar sound as it is, but really hard to position correctly according to the guitar. Hence my grade average after all. Damage.