I’ve never had a problem with it either, but my parents did. They had a problem with water leaking out of it, or it was clogged, or something was wrong that my dad pulled it off the sink and found some sort of white plastic had made it’s way into the discharge and hardened. He called up ISE and the first thing that they asked was if he dumps boiling water down it. When he said yes, they told him that he melted a liner in the disposal and that was the problem. He was also told that he voided the warranty by doing that. But they replaced it for free when he said that it would be stupid if he had to go and drain the pasta at the neighbors house. They wound up covering the disposal and sending a replacement (ISE is usually VERY good about sending replacement disposals if yours breaks). Anyways, while it generally isn’t a problem, whenever we dump boiling water down the disposal (or any drain for that matter out of habit) we run the cold water at the same time to help cool it off a bit.
Generally speaking, a garbage disposal is a plumber’s best friend. They are seldom used properly, which leads to clogged pipes. If you talk to anyone who has maintained a multi-family housing complex, they will generally curse the day someone invented the evil things.
Of course the apt owners kind of shoot themselves in the foot by buying the flat out cheapest disposer on the market, the one least likely to be able to put up with abuse. The one that gets used by people most like to abuse it.
The difference between you average bottom of the line disposer, and a good unit is night and day in all respects, noise, efficency, vibration.
I can second the warnings about potato peelings. I’ve only recently acquired a waste disposal (it was already in the new house) and it is possibly the most useless applicance ever invented. Yes, it is handy for washing bits of food off plates, but for anything bigger it is much slower than just tipping it in the trash. Compare: trash can approach - scrape into can. Waste disposal - scrape into sink; run water and chase bits around with the hose-jet; resort to fingers for those things that still won’t wash down; switch appliance-of-Satan on and off at whatever the appropriate times are. But, not wanting to appear to be a Luddite, I did decide to give the WD a try and chose… potato peelings. One flooded kitchen and plumber’s visit later, I have decided never to use the thing for anything bigger than grains of rice.