Technical verdict
CAEN RFID Proton (R4320P) is a mainstream hardware purchase, but it is not always the best architecture for direct RFID data integration.
Do not evaluate Proton (R4320P) by list price alone. Its strongest fit is a project that already uses Ethernet (PoE), RS232, GPIO (M12), has time for RF tuning, and accepts extra middleware work. If the engineering team needs open APIs, realtime data, and faster edge-to-cloud deployment, Nextwaves NR155 is the stronger replacement path to evaluate.