I was happy enough with them, but they just went to [poop]
I had a Roomba i7+ for a long time (the + means it came with a stand to charge and empty its bin), and it worked great. Every day it'd run around and happily clean up all the new shed cat hair and spilled kibble and knocked around cat litter, then empty its bin. I only had to maintain it and change the bag about once a month. Even while we were gone on vacation it would keep cleaning! Perfect when you have cats. You could get replacement parts (bags, rollers, filters, etc) way cheaper from third parties than from iRobot. Sometimes I'd actually check the bin before it emptied into the bag and was amazed by the amount of cat hair. Where the heck was all this coming from? I sure didn't see it. So it was nice that it was cleaning stuff that I wouldn't have noticed, like under the bed, every single day.
Well after about 6(?) years the i7+ was obviously going senile, battery going to poop, so when Amazon had a Black Friday sale on the i9+ I snagged one for half price. Hey, it's two more, must be better, right? No, it was a total piece of crap. Things the i7 would handle with ease it kept getting stuck on. I had no obstacles near the stand, completely clear for it to roll onto it, but it kept failing and insisting it needed to be placed back on the stand by hand. While the i7 could go a whole month cleaning without intervention, the i9 had a successful run rate of about 30%. I'm not sure /exactly/ what made it so much /worse/ than the older model (vibe coding?) when even just the same would have been fine, but iRobot's stubborn refusal to add LIDAR, Elmo style, certainly didn't help.
Anyhow, for Black Friday this year I grabbed a Roborock Qrevo and yeah, it is just light years ahead of the Roombas. It has LIDAR and actually doesn't smack into things, it's far quieter, it has SO many more options, it's never gotten stuck yet, the app is far, far better. So once again I have a vacuum cleaner that runs every day and cleans up the pet hair, kibble, and kitty litter. Of course the downside is that Roborock is Mainland China, needs their app, and needs wifi to talk to it. Well, I'm not putting that on my internal network (ditto for the Roomba!), so I put it on my separate doghouse AP that doesn't get to see my internal network. That's a really good strategy for any stupid appliance where you actually want to use it with an app.
Anyhow, yes, iRobot's products sucked. iRobot coasted on their initial superiority for far too long and deserved to die.