Seymour Duncan Acoustic Tube Pickup

I purchased the Acoustic Tube Pickup to put in an old but "dear to me" Goya acoustic (lic. by Martin)that I didn't want to mutilate to put in a normal pickup. I like it great. It has a reasonably flat response across all strings and the built-in volume control is really neat. No batteries to go dead if you forget to unplug it. It is easy to install and can be moved from guitar to guitar with 10 mins work. Only downside is that the output is lower than from a preamp style pickup.