Fully digital. Lol. I've had nothing but trouble with the digital passport readers ever since they went live.
Talking to the good people that actually work the border, the problems partly stem from the paper and laminate being used, in many passports (including British ones). They are too reflective so the scanner often struggles to do anything - necessitating you leaving the electronic queue to join the meatbag queue instead.
Dropping paper means going for some sort of silicon or magnetic format instead, which in either case the potential to break is vastly more obvious to break than the extremely hard to forge paper setup. Full digital by contrast - buy an appropriate flash ROM burner and you're good to go.
Like ballot papers, sometimes simple is the best and most secure solution. Don't just go digital because marketing. Throwing people at a problem instead of a giant IT exercise may well be more effective and cheaper.
Biting the hand that feeds IT
