When I received this item I tried to display my Windows 8 tablet. It did not work. I needed to update the firmware on the unit in order for it to properly work with Windows 8. That was a pain since I couldn't connect to it. I eventually had to connect to the wireless SSID and then with Firefox update it. It didn't work with IE which is not indicated on their site. Then every new PC to connect needs the wireless and WIDI drivers updated. PAIN!!!
Miracast with Android works rather well. Some lags probably due to wireless interferences. I cannot get Win 8.1 tablet to work most likely due to Windows's problem. I have not yet tried Win 7 Notebook WiDi
The price is rather high for Wifi Direct only (but it does work without any fuss). It could be better if it also support DLNA.
It is usable for me but not really worth it.