Just also bought a H11B to upgrade from the H9B. Was considering the mini given I practically never use the screen, but decided against it given the issues i've had in the past trying to get the damned thing to work with my phone.
10bit colour, better low light, better hypersmooth & superview at 4k res, with higher bitrate. Should be a good upgrade.
All the footage/audio i've seen from the Insta360 X3 looks garbage still. Shame.
You'll notice a massive difference in touch screen response and camera speed. The GP2 processor in the Hero10 was a massive jump from the Hero9.
Foam Ranger tried to compare and give the Insta360 some creed but couldn't lie... settled for better audio on the 360.
Not only horizon levelling but horizon lock at 5.3k. The Osmo3 has still only got lock at 2.7k same as the Hero10. Horizon lock lets you rotate the camera 360° and keep the horizon level.
The other big deal is Hyperview, squashing down the 8x7 picture to 16x9 shows so much more trail ahead and handlebar/bike than superview.
Hypersmooth 5.0 has a boost mode that works smart, reducing the FOV when the camera is being shaken vigorously, increasing it on the smoother stuff.
The max bitrate is also went from 100Mbps to 120Mbps and the 10 bit colour takes the GoPro colour range from 16.7 million to 1 billion colours.
Sounds like it will be a lot better but we'll see.
Most are saying it's a big upgrade from Hero9 and below, Hero10 for the common backyard hack (me) they wouldn't bother.