Have a look at this 10 second video.
The magnetic collar on a Commodore disposer is inspired. You do not have to worry about silverware, wedding rings (unless you want) or anything metallic being chewed in your disposer
How to buy a disposer:
1. Type: There are two types, batch and continuous feed. Batch is turned on by a a cover, and continuous is activated by a switch. Conventional wisdom says batch is safer, but continuous is easier to use.
2. HP: Horsepower dictates the speed of the grinding. More horses (and the best is 1 1/4) means better grinding capability.
3. Warranty: Runs the gamut from almost none to lifetime.