I have owned this product since March 2012. This product has-been used with many combinations of PA systems and always (after a quick set up) Performed faultlessly. It has allowed different combinations of speakers to be controlled to end up with a fantastic sound tailored to the music Being Played Rather than a generic top end heavy sound. The only critisism of the product is the human interface Is not Always the Clearest to use and the auto calibration function needs to be taken with a pinch of salt - this can always be corrected manually though.
Fantastic product - I wish more people HAD em Their ears Would you thank 'em.