I have a fiber optic switch, which is just like an air switch, only it has a sealed gasket so water can't go down it. Like air switches, fiber optic switches are available in several finishes. Waste King made mine, but it works with any brand of disposer. You should be able to see one in a store that sells Waste King GD's. You can buy them online, too, and much cheaper than in the store. Either an air switch or a fiber optic switch is much easier to use than a switch in the wall or under the counter.

the switch, either air or fiberoptic, is not hooked up in any way to the disposer. It is plugged into the disposer outlet, and then the disposer is plugged into the outlet on the switch outlet box. so you can use this switch with any appliance that plugs into the wall. I added a picture of cheap one I found on amazon. You can see that there is a cord that plugs into a regular outlet, and a box with two other outlet receptacles on it that you will plug your disposer into. there is a length of tubing, and a button that gets installed on the countertop. if the switch stops working: 1. check that it is plugged in 2. check that the GFCI did not trip 3. check the plastic tubing to make sure it is secure 4. unscrew the button from the counter top and clean it it is a very simple device and is worth $20 at most. Just buy the cheapest one you can find in the finish you want. a homeowner can easily replace it. the fiberoptic ones just use a touch sensitive pad rather than a mechanical air switch but install the same way and fit into the same size hole. these cost about $75.

Unfortunately, my mom is in her final days and needed me to care for her for several days after her birthday party. She's oxygen dependent (on 5+ if that means anything to you) and the power company turned off the electricity for the entire day without notice. Fortunately I was there and we made the switch to a portable unit - actually 2 since the first wasn't working properly. The oxygen company was great and put in an emergency order for an oxygen unit that provided continual feed. It was a scary day. Somehow the garbage disposal switch didn't seem like a pressing question. Really though, the cabinets should be here in about 2 weeks, so things need to be done and decisions made (we're DIY'ing). I'm leaning towards going with the air switch, but I still need to consider that more carefully. I really appreciate your sharing what you found out.

I considered the fiber optic switch, but opted for the air switch. Given that I wanted the button next to the faucet on the granite, the pivotal reason was that my fabricator can't really drill a hole smaller than the size used for soap dispensers and air switches. The fiber optic switch is smaller, but it still needs a housing to "plug" the unnecessarily large hole in the granite. And it costs significantly more. As to installing an air switch on a vertical surface: why not? As long as you can thread your tubing from the push button location to the power module, it should work regardless of the orientation of the button. See gnancy's diagram.