The point of the Pi setup is that you just don't have to worry about it. I've been using this for over two years now and only once when I needed to urgently see the video on my PC did I remove it to manually transfer. The rest of the time the videos get archived to my NAS and left alone. Speed of that transfer isn't important as long as it gets done and I don't have to sit around waiting for it.
Normally I view alerts in the car and delete as needed. However if I'm short on time and can't review them or want to save them, I leave them alone and let the Pi transfer them to my NAS later. I have a scripted program that runs every night that then processes the videos into a single MPEG file and speeds up the playback. So if I then review on my PC later, I can more quickly check them. Another script then automatically deletes them after a few months. The whole process is automatic from recording, to transferring, to processing and then purging.
I haven't fully tested it, but I don't think I've ever had the Pi corrupt or loose a video. It seems to wait to delete each of the recordings until all have been successfully transferred. The Tesla itself corrupting recordings is much more common of an issue for me then anything else.