46% of 26 verified Oral-B iO Series 9owners don't recommend it — based on real owner comments from Reddit, enthusiast forums, and YouTube.
For balance: 42% recommend it. This page collects the complaints so you know what you're signing up for — read the full owner report for both sides. How we score
“I find it crazy that the charging case isn’t USB-C”— @omgisthatvik on YouTube
“I highly recommend getting series 3 and saving your money!”— @powercoder on YouTube
“I have 3 toothbrushes of the new models, and all of them had a problem with the battery in a short time”— @rinagoren7499 on YouTube
“the battery will stop charging”— @TheGheddon on YouTube
“Not having usb-c on the travelcase was the reason i want with a phillips”— @Ghulliez on YouTube
“Mine did not work after two years, just after the warranty expired”— @CristianVasquez on YouTube
“I bang my brush head in the sink and black mold chunks come out from all crevices. It's so disgusting that I put that in my mouth.”— AFunkinDiscoBall on Reddit
“I've had the iO Series 9 since 2023 and I can say that the battery life on these things are garbage”— Substantial_Act_4499 on Reddit
“it was BLACK inside. Like not spots or chunks. It was completely covered. I almost threw up.”— lechatgris19 on Reddit
“I agree I've had this issue with the IO9 also, it slipped out of my hand into the sink”— PrehistoricEarth on Reddit
“I am on my 3rd one within 2 years. The quality, build and QA is not the same.”— Hungry-Baboon on Reddit
“I’m a new series 9 user and one thing drives me crazy: I finish a brush program and then I want to switch modes to use the tongue cleaner mode, but I can’t find a way to switch modes other than waiting 30 seconds for the device to turn off and then I’m able to select mode when I wake it up again.”— Romhe on Reddit
Not complaints — practical notes from owners that didn't affect the score.
“I have had an IO series 9 brush at my home and have dropped to approximately 30% remaining battery with only 12 brushings.”— Alex Boomgarden on Electric Teeth
“i just bought it and its not connecting to the app its just detecting it.”— harvey on Electric Teeth