Virginia went back to paper ballots and optical ballot scanning several years ago. I think the only drawback to this approach is storing the ballots for X years after an election (takes up space). But, it's far more secure and easy for everyone to do. Just like taking a high school test... pencil in the circle. https://en.wikipedia.org/wiki/Optical_scan_voting_system
One of the models (the ES&S M650) might be the actual scanners you are talking about, and that model has a number of terrifying vulnerabilities!