Start with the sink, not the spec sheet. A garbage disposal comes in continuous feed and batch feed styles, and the style you pick decides how you use it every day.
What each feed style asks of you
A continuous feed unit runs while you push scraps into the top. You keep the water running and feed in small amounts. It suits a cook who clears each plate as it comes and wants to drop peels in without stopping.
A batch feed unit uses a lid or stopper that you fill and seal before the motor starts. It adds a step each time, and the lid works as a guard. Many households with children, or with a crowded sink, choose this style for that reason.
Check the sink before you shortlist
Look at the sink flange and the drain opening. Measure the mounting ring, since the mount has to match your sink. Note whether the dishwasher drain hose joins the disposal inlet, because that connection changes the install and the service path later.
Compare the parts you will touch
Ask which parts you will reach by hand. Look at the reset button location, the access to the underside, and whether the unit has a hex socket for turning the motor by hand when it jams. A unit you can clear without tools is easier to live with. Ask the seller or installer to point these out on the actual model, not only in a photo.
Test the claims against your kitchen
Words about power and grinding describe a test rig, not your sink. Write down what your household puts down the drain most often. Fibrous peels, bones, and coffee grounds ask different things of a disposal. Bring that list to the comparison and ask how each model handles the items on it.
For typical service life and the planning date it gives, see the garbage disposal guide. Set the date from the install year on the unit, then compare models with that date in view.