We have had two Kitchenaids (changed to stainless one). No problem with either. My daughter had a different brand and had a problem. Not sure which brand but it had two valves one for hot and one for cold. The hot water side plugged up some way.

I have a 7 yr old insinkerator hot/cold with a brushed nickel finish.

We had a problem with water leaking out the hot lever last year, and they sent an entire new unit for free.

Here is a link that might be useful: hot/cold dispenser

I have had two Insinkerator hot water replacements installed since our original installation in 1994. The reason for having replacements is because eventually the bottom leaks... (think of it as a hot water heater... eventually they all break). Apparently mine had a slow leak that we didn't discover until it had leaked all the way down to my basement below and lifted up some of the tiles down there. We had turned it off for a while before we fixed it so we could sell our home with a working appliance.

Since we now own a Keurig coffee machine, I prefer to get my hot water for my tea from that instead.

I will not be buying or installing one of these again in our new build since we love and use our Keurig machine.

I have decided it is just one more thing that can break down that isn't necessary.

7 years going for me, using an Insinkerator brand. This is probably my favorite kitchen upgrade. We use it several times daily, all year long. Warm up AM coffee cups, quick rinse of dishes and the occasional dog licked plate.
I also had one slow leak from bottom a couple years ago, no damage, but I now keep an old bowl under unit, just in case new leak develops.
I also recommend a water filter in line between instant hot and city water supply. I think this prevents early failure and like that my drinking water from cold lever from instant hot faucet and line into refrigerator is filtered. Make that double filtered since refrigerator has it's own filter.

I plumb RO water to mine. I have a Miele built in that makes hot water too, but I don't want to leave it on all day given the difference in cost replacement. I use it for all sorts of tasks, but especially cleaning. Hot water just works better.