Recent standard for best touch-screen technology ? (big screen for Ticket Vending Machine)

We need to order new Ticket Vending Machine models (for train tickets). We know from our research that our customers complained a lot about the quality the touch screens of our current models (e.g. not precise enough when pressing on certain elements - or degrading precision after a few years-, poor display in case of sunlight reflection, ...). We would like to make sure that our next displays will offer a better experience in that matter. But as technology in such an area rapidly evolve, I have a hard time finding recent standards that define which type of technology/screens would make a good bet (indeed, touch precision is defined by the technology behind, the sreen size, etc.). Sure, there exists a few ISO standards (ISO 9241-9, ISO 9241-3, ISO 9241-5, ISO 9241-7 or ISO 9241-2) but they've all probably become a bit outdated in such respect. Do you have any experiences or sources you would be willing to share regarding this ? Thanks a lot.