The Fat Gecko looks like a great mount, I am sure you would get great internal shots like the POV and driver shots, but when it comes to outside I am sure it will not handle a track day, or even a drive at speed.
When we mounted cameras, we always used a very small camera for the outside because if you using a single or a dual point mount, the camera needs to be something like a single chip Bullet Camera, this helps get a great shot because of the size and its stability. Theres no point have high def pictures if there is a lot of vibration from the car and the wind !!
Here is a bullet Mini Bullet Outdoor Waterproof Security CCTV Camera on eBay (end time 17-Jul-10 22:16:26 BST)
The nice thing is you can cable tie (and a bit of gaffer just to make sure) the camera to the front bumper for the very low fast shot. If you damage it, its not hugh amounts of money for a new one.
If you have a camera that has a input on it you can record to that very easily.
If you have a medium to large camera you need to have a three point mount. it works on the same principle as a tripod. I have had a Sony Z7 on a tripod with 3 suction mounts (1 per leg) and for extra precaution I used a ratchet strap with another suction cup on its own as a tie off for the camera. And had a long shot down the bonnet catch the drive and down the right side of the car.
Here is the way. http://www.cinemagadgets.com/images/027_5022.gif
Here is a example of how to mount the right way
Now when it comes to shooting lets say Top Gear they would use something like this
Creative Video Sony HXR-MC1P (HXRMC1P) HD Minicam with solid state AVCHD format recording system + FREE 8GB MEMORY STICK
My only tips are when apply the suction mount to the body work is, make sure the suction cup is free from damage, and clean both surfaces well.
If you decide to get the gecko I would buy both mounts and use the mini to help brace the larger camera mount to make that triangle of support.