I have found the "under the saddle" pickups to work well as in "electric guitar", but then you can no longer play acoustic (unless you change the saddle). If you have a quality sounding acoustic guitar this is not the way to go. The cheap new Martin guitars with onboard electronics sound great plugged in and I highly reccomend them, but they sound as bad as those O'plastics otherwise. I compare the success of a pickup with the great sound of a Sure 57 and its associated frequent feedback. I had always used a 57 for my D28 and just rationalized away all the down sides untill one day I began trying different mikes on a stand up bass. Great results were obtained using a Radio Shack lavalier with long cord. The cord and preamp are included for under $25. That worked so well I tried the Radio Shack wireless Electret Condenser lavalier inside my D28. The transmitter-preamp-antenna-powersupply-mike-AA-battery combo is only a few ounces. I turn it on, dump the entire thing inside, have no wires exposed, and it sounds great. (Frequency Response 70-10kHz) If I have to work close to a very hot studio mike I also install one of those heavy rubber soundhole covers to completely eliminate feedback. Under $70 and when I dump it back out I still have a great sounding acoustic guitar. I will agree with the pureists (of which I was once) after reading this, will comment that here we have a rather rinky-dink approach to a problem which is usually not overcome even by throwing money at it. This works very well for my D28 guitar, F12 mandolin Gibson banjo, fiddle and bull bass. What I like beyond the convenience and not having to drill holes in classic instruments, is the warm quality sound without being muddy. And all the instruments remain and retain their acoustic value. These wireless units are available in either 49.830MHz or 49.890MHz and can be used at the same time. Cheers!