For crashy tracks, the best camera mount is usually the one that protects the camera first and gives you just enough damping to keep the image usable. If you are running a lightweight micro camera or a small HD freestyle cam, a TPU mount is often the sweet spot because it absorbs shock without adding much weight. TPU is flexible enough to survive repeated tip-overs, but it still holds the camera firmly if the design has decent side support and the screw holes are reinforced. A mount that is too soft can let the camera wobble, which looks bad on video and can make the lens hit the frame in a hard strike.
If the track is really rough and you expect constant contact, look for a mount with a low profile and some built-in protection around the lens. The camera should sit as far back in the frame as practical, not sticking out like a handle. That small difference matters a lot when you slam into a gate or roll through dirt. A mount with side cheeks or a small front lip can save a lens from taking the hit. I would also favor a design that uses two mounting points instead of one, because a single-screw mount can rotate under impact and point the camera at the sky after a bad landing.
For larger analog or heavier digital cameras, harder TPU or a semi-rigid nylon-style mount can be better than soft rubber. Purely soft mounts may protect the camera, but they can also make the image messy at high throttle or during fast direction changes. On a track, you want a balance: enough rigidity to keep the camera aimed straight, enough compliance to survive crashes. That balance usually matters more than chasing the softest possible setup.
Another thing people overlook is angle adjustment. If you race steep tracks, you may want a mount that lets you set 10 to 25 degrees precisely without stacking a pile of washers or zip ties. The cleaner the setup, the less likely it is to shift during a hit. Also, check whether replacement parts are easy to get. On a crashy course, mounts wear out, and a cheap replaceable TPU piece is far better than losing a whole camera because the mount cracked at the arms.
My practical recommendation is to start with a strong TPU mount, keep the camera tucked inside the frame outline, and avoid anything tall or decorative. If you are crashing a lot, durability and retention matter more than the last bit of vibration damping. If the footage is still too shaky, then adjust props, tune filters, or add a little more soft isolation, but do not make the mount so squishy that the camera can move around in a hit. That is usually where people run into trouble. If you have a specific camera model and frame, share them and people can suggest a mount style that fits the size and crash level better.