cheaper doesn't necessarily mean worse. a lot of effort has been put into making the screens suitable for a wide range of demands that may include, depending on brand, 20+ point touch, over-the-air updates, built in Android, low blue light panel, extra connectivity, Wi-Fi, software suites, anti-bacteria hard glass, wider range of sizes, RFID sensors, multiple pen colour recognition, hand gestures, I could go on.... but hopefully you get the idea that's it's more than just a screen to replace an interactive whiteboard.