This is a great product for giving the guitar the extra bite and mids.
A word of advice: when installing this, don't set the boost at maximum (you'll understand what I'm referring to when you're there). I had it on max and it just made the guitar sound terrible and over distorted (much like the "loudness-mastering" on Metallica's Death Magnetic). Begin at 50%, try the guitar throught the amp and adjust upwards if needed.
Also, think about this before installing it: do you want it to activate when flicking the switch down or up? If you know that, you can put it in the right position from the start.
I wish I had this boost in all my guitars...