True story, several years ago we upgraded our ISP plan and was trying to get the family on better wifi speeds - unfortunately in my townhouse community we are close to town and the wifi is very crowded (over 400 APs visible in wifi scanner!) and had big problems getting a stable wifi connection in just about every device.
Tried expensive adapters like that Asus in the $100+ range (was not AC3100 at the time, I think it was 1900) but also didn't work, also tried upgraded routers with matching speeds to no avail.
In researching I came across an article,
Review: Ubiquiti UniFi made me realize how terrible consumer Wi-Fi gear is @ ars
Said "why not" and gave the AP-AC-LR a try, was $120 at the time - once I disabled my router wifi and fired it up, located near the center of the house - I now get 5ghz full bars in the entire townhouse (save the farthest room, drops 1 bar) and also get 1/2 strength in the backyard. Rock-solid stability @ AC1200 max, with over 2 dozen active devices with the help of extended family visiting to test it out.
A side effect, the cheap budget adapters and old laptops now work very well!
Both of my sons PCs are now using an AC1200 adapter similar to
this one with a weighed desktop usb3 cable, the
StarTech 5 ft Desktop SuperSpeed USB 3.0 Extension Cable. The adapters report a 400mbps connection and real world speeds that max out around 40MB/s (320mbps). Could not be happier, no problems playing FPS games with them at all.