I won't deal with anyone except Doyle and Ruth Finch. If you know where the Birch Run outlet malls are, you can find them.
Take I-75 to the Birch Run exit. Go east (if you are coming from the south, that would be a right turn. The first four-way traffic light will be Dixie Hwy (US 10). Turn right. Immediately get in to the left lane. About 1/4 of a mile, on the left side, you will see a tiny white sign that reads "metal detectors."
Doyle is now blind but they have a small shop/museum out back. He knows what he is doing and service is great. He will even let you rent a machine to "test" it.
Search the white/yellow pages for Finch Products/Birch Run.
Bill