Technical verdict
ThingMagic (JADAK) Sargas (4-Port) is a mainstream hardware purchase, but it is not always the best architecture for direct RFID data integration.
Do not evaluate Sargas (4-Port) by list price alone. Its strongest fit is a project that already uses Ethernet, USB, Micro SD, 8 GPIO, 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.