What I meant was, it works, but nowhere as well as the cheapest cordless phone works. No consumer electronics company could sell a dedicated cordless phone that worked on WiFi -- too many customers would return it. If you think you're having trouble with DECT, imagine all the other WiFi radios within range of you right now. And, as soon as somebody starts streaming Netflix or some torrent, fuggedabodit. The WiFi 5GHz band has poor signal propagation qualities, and is quite short-range.
Bottom line: try it on an Android phone or iPhone. You'll either be happy with it, or hate it.