So far the TP-Link AC750 RE220 Dual-Band WiFi Extender (2019 release) has worked great and suits my needs perfectly.
It's small and visually appealing so you don't need to worry about hiding a bulky or ugly device. It actually resembles an plugin oil diffuser like a lot of us might have. It is very light weight so it shouldn't sag from the outlet when plugged in. You will lose an outlet plug and if that's a problem you can always use an extension cord and put it where ever you want. The front of the RE220 boasts 5 easy to understand LEDs informing you of its status (power, ethernet, WiFi, 2.4 GHz and 5 GHz bands) and a WPS button. The bottom of the device has a high speed RJ45 ethernet port (this is absolutely golden for wired devices) and a reset button which is recessed so you don't have to worry about accidentally pushing it and ensuring that you have to mean it when you do use that feature. It is supposed to work with any WiFi router. The mobile app and web user interface also give you management options like enabling the High Speed Mode, restricting particular devices for a specified amount of time and it even lets you turn off the LEDs if they might disturb your sleep or distract you. I personally have not used the extra features as of yet but they sound like they might be pretty useful, especially being able to turn off the LEDs. I think everyone has noticed blinking lights from various devices and they can be super annoying if they're in your bedroom or visible when you're trying to focus.
The RE220 was very simple to set up with easy to follow step-by-step directions in the box, which guide you through the process and inform you about your options for setup (WPS, mobile app, web UI), where to find the app, a QR code for the app (this is also printed on the box) and the web UI address for setup if you opt to use a computer instead of the app or WPS feature. I chose to use the app which is also very simple which made the process all the more enjoyable. All you have to do is follow the on-screen prompts and it goes smoothly. It has you setup your 2.4 GHz and 5 GHz WiFi bands separately as they each have a password although it's usually the same and it's also true that not all networks are dual-band. I didn't have a single problem during setup. It was quick and painless.
The only setup issue I did have was mine. In my haste to get the RE220 going, I didn't rename the extender's WiFi signal to match my home network so it caused conflicts with my IoT devices that were trying to talk to each other because the network is password protected and I had actually created a second password protected network. This caused some communication issues. The instructions even tell you that you may want/need to do this but I was in a hurry so I could get other things done and overlooked that. Once the signal was renamed and the password set to match the original network it worked great and without issue. This was very easy to do within the mobile app but could also be easily done using a laptop or desktop computer.
I bought this to solve an issue with a device I got a great deal on. I stumbled upon a used Sony Media Streaming Bluray player for $15. I couldn't believe it and couldn't pass it up. I didn't really need it but I was tired of using my phone or laptop to stream movies and video to my bedroom TV. It was always a hassle and the only alternative was a wired connection directly to the TV and that in itself was a pain and more so if I wanted to play any of the discs that I have since my laptop doesn't have a built-in disc player and I have to connect the USB BR/DVD/CD player. The problem was that the player required a wired network connection and not wireless. I can't complain since it was practically free. I don't know about you but my house does not have wired ethernet. I could do that myself but it's time consuming and the money needed cancels any value in my purchase, in fact, it probably would have exceeded the cost of a brand new media player and I didn't want to make that kind of investment just to get a media player on the network. My TV is a few years old and it doesn't have WiFi or smart apps itself and I'm not ready to spend a few hundred just to get that kind of experience there either. Not when I can work around it for much less. This network extender allowed me to connect the Bluray player to the network using a spare network cable that was laying around from an old printer or maybe it was an outdated gateway from an internet old service provider. Regardless, the cable was brand new in the package and all I had to do was plug it into the TP-Link RE220 extender and my Bluray player and BAM the player was on the network and asking me to install updates. To top it all off, the WiFi signal in my bedroom is much stronger and everything using the RE220 signals have a much more reliable signal. That's not to say my Arris Gateway didn't give me a good signal to begin with, it's just a stronger signal.
The speed of the TP-Link RE220 AC750 WiFi Extender works great for watching Prime videos in HD. I get full 1080p just fine. There is always a loading delay but I think that's the player which is a few years old so the memory and processor speed is not top of the line but it was $15 so again I'm not complaining. If you plan on watching 4k Ultra video, you may want to do some research to see if the TP-Link RE220 AC750 WiFi Extender meets your needs speed-wise, but it claims 433 MBps for 5 GHz and 300 MBps for the 2.4 GHz bands which should be fast enough but it's not GigaBit speed for sure. I don't have a GigaBit speed router so it wasn't a concern. My TV isn't 4k Ultra capable so I didn't worry one bit about it. I did notice that when I watched a movie using the Amazon Prime app on the player, it checked the connection speed and displayed the result and it's exactly what I see on my Samsung Galaxy S9+ on the home WiFi so the RE220 does not seem to be slower than the Arris Gateway my network is running on to begin with and the only speed issues I ever see are when too many devices are simultaneously using too much bandwidth (multiple HD TVs, cell phones, laptops, remote set top boxes, etc). First world problems...am I right? The only solution there is a faster internet connection and router which hasn't been necessary and saves money and even if I did upgrade I think this WiFi extender would still suit my needs.