@Serse Set MR200 wireless mode to 802.11n only for optimal performance. I would experiment with different static wireless channels to check if there's an improvement.- the wireless channel may...

@Rignus If you need more powerful router then use the BE25 as a main router with M5 connected with a wireless backhaul. This way you'll have a mesh and seamless roaming. C7 can be attached to one of...

@Awddrake94 EX230V is an ISP provided device and it's quite possible that its firmware is customized for the ISP. This could be the reason after reset the default password to be different than the...

@johnvick2 When configuring RE200 (use this guide) select the "Copy from Main Router/AP" option to have the same SSID on both 2.4 and 5 GHz bands.

@Filip123 EX220 is an ISP router, most probably with a customized firmware for your ISP. This could be the reason after resetting, its wireless SSID to be the same as before. For more details on that...

@Serse Ideally, your wireless settings should look like this: