I love the idea of the card, and making the runner choose to take damage over the course of the run, or face losing hand size. The runner has to gauge the likelihood of a trap in this case more than normal. It used to be, break everything, and have 2 cards per advance. Now you can't necessarily do this, and might result in them jacking out, leading to a score.
Fair rez to trash ratio, once the build comes out for this, I think it will be a solid 1 of, with maybe on 2 of. 3.5/5