If it supported powerline networking and had better overall performance, the Netgear AC750 WiFi Range Extender EX6100 would be a great networking device. As a pure Wi-Fi extender though, it's both awkwardly designed and underpowered.
That makes for a disappointing combination. While it does extend an existing Wi-Fi network, its Wi-Fi data speed is fast enough only for simple Web browsing and not suitable for online gaming or media streaming. I can't recommend it at its $90 price, especially considering that it ran hot in my testing, not to mention taking a long time to boot up.
In the end, it's better in its secondary role as a dual-band Wi-Fi access point. But even then, there are other, better options out there. For those living in a home with a single electrical wiring network, I'd recommend the Actiontec PWR51WK01, which is cheaper and delivers better performance.
Awkward design meets low-end Wi-Fi tech
On the outside, the EX6100's awkward design resembles nothing so much as a huge plug-in AC power adapter with two protruding antennas. The idea is that you can just plug it into a wall socket and it's ready to go. However, when you do, chances are you won't be able to access the adjacent plugs, which are blocked by the extender's bulky body. This type of power adapter-like design is popular with powerline adapters, which must be plugged directly into the wall to work. The EX6100 doesn't support powerline networking, though, and it would fare just as well with a power cord.
I don't like the guts of the EX6100, either. The device supports just a single-stream setup with the 802.11ac Wi-Fi standard. This means its top theoretical speed on the 5Ghz band is 433Mbps, rather than the 1,300Mbps an 802.11ac device should be capable of. Single-stream is generally used when you need to save power, such as a mobile solution where battery life needs to be extended. EX6100 is not battery-operated, so I don't know why Netgear doesn't configure it for a faster 802.11ac spec. On the 2.4GHz band, it supports the dual-stream setup with the 802.11n standard to have the top speed of 300Mbps. (Read more about Wi-Fi standards.)
It's generally tricky to find the right spot to place a Wi-Fi extender, but the EX6100 makes this process easier. If you place it too far from the original router (or access point), you'll get no improvement in range since the signal of the existing Wi-Fi network is too weak to be meaningfully extended. The EX6100 does come with a handy indicator light that glows if the device is too far from the original router. Unfortunately, since you need to plug it into a power outlet for this light to work, and the extender takes a long time to boot up, it can be frustrating to test it in different spots around the house. And depending on your luck, you might be able to find a wall socket in the sweet spot that's not too far but not too close to the original router. Otherwise, you'll need an extension cord.
Easy setup, but just one Wi-Fi network at a time
If your existing router supports Wi-Fi Protected Setup (WPS), you can connect the EX6100 to it within a few seconds. Just press the WPS button on the router and then the one on the extender, then wait for a few seconds, and you're done. The EX6100 is now connected to your existing Wi-Fi network and will extend the Wi-Fi via its own Wi-Fi networks. Note that the EX6100 doesn't repeat the existing network name, instead it creates two Wi-Fi networks of its own, named after the existing network with "5GEXT" and "2GEXT" suffixes, both of which use the same password as the original.
I tried the EX6100 with a few true dual-band routers and noticed one odd thing: with WPS, the extender always automatically defaulted to the 2.4GHz band network to connect to rather than the faster 5GHz band network. For this reason, it's better to use the Web interface or the Netgear Genie mobile app for the setup process. This is also the only way to set up the EX6100 if your existing router doesn't support WPS.
It takes a little longer time to set up using the Web interface, but the EX6100 comes with a very clear instruction booklet so the process is easy enough.
The EX6100 comes with one Gigabit network port. When working as an extender, the EX6100 can use this port to connect a wired device such as a game console to the Wi-Fi network, effectively making it also a Wi-Fi bridge.