Still using a Alfa AWUS036ACH for a wireless connection: 802.11ac wave1 from 2015.
There's simply nothing better available, in 6 years of intervening time.
This world would be so so much more awesome if there were some really really good USB wifi adapters. This is yet another further leap, but I also think of all the guides to turning the RPi into an access point, via usb adapters: it starts out working fairly well, but the hardware either has hard maximum client limits or just fails to work well once you get to half a dozen devices. Even if you have something like PCIe or M.2 expandability, options are still extremely limited, & availability is incredibly poor.
I'm a huge fan of Alfa gear, for a long time. They do an amazingly good job.
AWUS036ACH is one of Alfa's most up to date USB cards. It is, however based off an RTL8812AU chipset[1], which is 8 years old now[2]. I'd love at least to have a good client chipset & equipment that supports WiFi6 that has good RF performance. I still think the market is overly structured & segmented. No one makes AP-class chips for USB, but to be honest I really think they could & should & that it'd be exceptionally useful & good. But no one dares to threaten the AP market like that.
Thankfully in wifi, RF engineering & antennas count for a huge amount. You still have great gear. But it does hurt me to see what seems like rampant tech-stagnation & neglect, of such a vital, interesting, basic part of modern communication technology: our wireless systems.
There's simply nothing better available, in 6 years of intervening time.
This world would be so so much more awesome if there were some really really good USB wifi adapters. This is yet another further leap, but I also think of all the guides to turning the RPi into an access point, via usb adapters: it starts out working fairly well, but the hardware either has hard maximum client limits or just fails to work well once you get to half a dozen devices. Even if you have something like PCIe or M.2 expandability, options are still extremely limited, & availability is incredibly poor.