@BEPPI  Hello, 

RE650 is pretty high-end model range extender and other range extender may not perform better than it on Wi-Fi range. 

Can you help introduce the environment in your house and how do you want to extend signal,  like the distance between the rooms & router, walls. Can you run any Ethernet cable / need wireless connect to router to exteWi-Fiifi?  Are all the rooms in the same powerline circuit/ same power meter?