Relatively speaking, the clip isn't that bad. You don't see much detail due to the crappy camera phone video and the distance the photographer was from the wreck. I've seen videos that were far more disturbing.
I didn't get into this series until Fast Five (the first one with the Rock). These movies are absurd, and a lot of the action is just over-the-top, roll-your-eyes level stuff. But they're terrifically entertaining in a just-go-with-it kinda way, the characters are very likable, and there is a genuine sense these people look on one another as family.