Not sure about the legality specifically of this new Wifi mode/modules, but a lot of the companies selling other RF modules bare certainly know what they are do

Not sure about the legality specifically of this new Wifi mode/modules, but a lot of the companies selling other RF modules bare certainly know what they are doing is in a grey area. The FCC allows hobbyists to build up to 5 devices for personal use, and these sellers usually justify it as selling development boards for prototyping. The FCC doesn't seem inclined to enforce much against hobbyists, which is how you get stuff like obviously complete products on Tindie being sold under the "development board" exception. Which I'm glad for as a lover of those hacker gadgets, but the FCC could always come in and shut it down. SparkFun for example definitely is aware: https://www.sparkfun.com/tutorials/398 https://www.sparkfun.com/tutorials/398