Beware Fiber Optic GD switch!
If you're getting granite, check this out carefully before buying a fiber optic switch!
OK, so when I read about the Waste King Fiber Optic Switch a few months ago, I was excited. The OP pointed out that since the gasket was sealed, you avoided the problem of water/soap that can get down in the air switch and disrupt it. Then Suzanne mentioned that her fabricator couldn't drill a 3/8" hole as required. So I asked about this. My fabricator said that he prefered not to drill small holes because when he tries, he destroys the very expensive diamond drill bits. So the place I bought the switch contacted Waste King Customer Svc (I was standing right there), asked if one could use a different sized hole, and they were told, "just drill a 1 1/4" hole and purchase the adaptor that we sell that modifies existing 1 1/4 holes. And yes," they said, "you have to do this, because it really needs to be in a 3/8" hole" (for some reason that was not explained). So I did buy this adaptor. $20(including shipping). Then I had the fabricator drill the 1 1/4" hole, just like Waste King instructed. Today, my GC is trying to install this, and clearly, this adaptor does not go in this hole. I called Waste King and was told, "oh that adaptor is for thin counters - it won't work on granite." AARRRRGGGGHHHH!
My GC is very creative, and he has come up with a way to make this work. But unless your fabricator will drill a small hole, DON'T BUY ONE OF THESE! Of course, it's still not clear why a hole of, say 3/4" or 1" wouldn't work just fine. Maybe it would.
Actually, the general incompetence of their customer service department suggests that one should not buy anything from Waste King.
Also, the switch itself is plugged, not direct wired, so my GC had to adapt the wiring to work with the disposal. What a pain. Stick with the air switch. It's also way cheaper.