For a writing speed of less than 2 GB per hour of video to Tesla Model 3, one would need an average writing speed of about 0.6 MB/s with peaks much higher. USB flash drives writing speeds are slower than reading. In principle, USB2 standard can go as high as 60 MB/s and USB3 standard as high as 640 MB/s, however, most actual drives cannot even get close to those limits. The writing speed also depends on file size. Sequential read is also faster and usually what is listed. 

Apparently, according to UserBenchmark, the SanDisk Extreme Pro 128 GB reaches around 260 MB/s write speed.

The SanDisk Ultra Flair USB 3.0 128 GB is advertised as up to 150 MB/s, and in tests has about 100 MB/s writing speed.

For lower price, you tend to get improvements of reading speed at the expense of writing speed. For exmaple, SanDisk Extreme 64GB and Samsung FIT 64GB have similar reading speeds (200 MB/s), but writing speeds of 180 MB/s and 60 MB/s, respectively. The SanDisk is 3x faster at writing large files at twice the price.