Hello Z00bs
Thank you for your enquiry.
The Roomba s9+ has 30% wider rubber brushes than the other models, which means that the rubber brushes go almost to the edge. Accordingly, it sucks up hair before it can even get into the wheels.
The Roomba s9+ also has a rear wheel instead of a front wheel where hair can hardly get caught.
In addition, what Marc_sander has already written. All parts are designed in such a way that hair can be removed relatively easily. The unique rubber brushes basically prevent hair from getting tangled.
Depending on the use, a quick check of these parts once a month is enough.
Best regards
Your iRobot Team

@Z00bs Seems dueltich has been improved: https://youtu.be/3YYr-q5rNL...

I don't have a direct comparison to older models but all the individual parts that something can wrap around are super easy to take out and disassemble so that you can just pull the coiled hair off to the side! Takes a maximum of 2 minutes... From my point of view, the best possible technical solution!