A:
No, this router will be just fine. I would make sure to use the 5G antenna for your fire tv and eco (make sure they are in the same room because the 5G antenna is meant for close range and the signal cannot travel through objects like walls and doors), and then use the 2.4G antenna for your cell phone and 2 other eco's. I have the n300 and I use an xbox on the 5G, then 2 cell phones, a laptop, and a chromecast on the 2.4G antennas and it works great.