Yeah, that sounds about like my past experiences too. I think a standard IDE PC hard drive is fine for most in-car applications, as long as appropriate steps are taken. If vibration is a concern, try taking some foam padding material (like the egg-crate looking stuff that they sometimes glue to the insides of cardboard boxes to protect the contents in shipping) and place it under the IDE drive. There's no reason you're necessarily required to screw the drive in to a mounting bracket - if doing so means the entire bracket assembly is going to be vibrating a lot in a car. Get more creative. I've seen people string wire through the screw holes of drive cages and use it to suspend the hard drive in place.