Loc: Southlake, TX, Billy Bob Ranch...
I've used one and it does work....you have to be careful with over doing it. Once that switch goes on it will call til the battery wears out. Study the types of calls...you don't want to call roost down when they are already down and walking around. Good luck!
Loc: fort worth TX
Even though I have never tried it (and never will) I was also intrigued to see if it was legal and found this.
Calling devices (including manual and mouth-operated), recordings, and electrically amplified calls may be used to hunt game animals and game birds, except electronic calls may not be used to hunt migratory game birds, unless allowed by special regulation.