What To Look For
Ultimately, several aspects need to be considered when choosing a USB Wi-Fi adapter. The first one is the adapter's maximum data rate. In other words, for the home user of Google Fiber at 1 Gb/s, an AC1200 adapter can be easily justified. But for the user with 10 Mb/s DSL, any N150 USB Wi-Fi adapter will easily outperform the connection. Faster hardware isn't necessary, since it can't be utilized for improving Internet performance. On the other hand, for tech enthusiasts who use their home networks for more than just Web browsing, faster Wi-Fi adapters will accelerate file transfers across the LAN if the other network interfaces are up for the challenge. Look for a USB 3.0 adapter (as opposed to USB 2.0) for its higher transfer rate.
The next aspect is the need for an antenna. Gone are the days of the DIY Pringles cantenna; premade solutions are readily available now. If your USB Wi-Fi adapter is going to be used in the same room as the router, than any compact adapter should have enough signal strength. However, in cases where the USB Wi-Fi adapter is used farther away, especially with walls or floors in between, than an adapter with a high-gain antenna is called for. This needs to be balanced against any physical constraints, particularly when a bulky adapter will compromise a notebook's portability. Also, some adapters come with a dock for ease of placement, which can be useful.
Make sure that your USB Wi-Fi adapter supports all of the 128-bit security standards, including WEP, WPA and WPA2. Also, certain manufacturers provide more complete software packages that are easy to configure. Many manage the Wi-Fi connection, replacing Windows' built-in interface. Look to see if your vendor of choice has released software updates for its previous products as a sign of commitment to long-term support. Finally, look at the warranty period, which can vary from 90 days to the product's lifetime.