The Fast Ethernet ports and lack of 5GHz Wi-Fi mean it cannot handle modern "Super Vectoring" or gigabit speeds.
After upgrading, your ZTE ZXHN H108N should behave like a new device. Here is the checklist for high-quality validation: zte zxhn h108n firmware etisalat high quality
If you are an Etisalat (now e& UAE) subscriber using the router, you have likely searched for ways to improve stability, security, and speed. The phrase "high quality firmware" is critical here, as using the wrong firmware can brick your device. The Fast Ethernet ports and lack of 5GHz