Still have the issue with the external wifi and RPi3. It works only short time and than disconnect.
[ 173.520788] usb 1-1.3.2: USB disconnect, device number 6
[ 173.521133] rtw_cmd_thread: DriverStopped(0) SurpriseRemoved(1) break at line 482
[ 173.829830] usb 1-1.3.2: new high-speed USB device number 8 using dwc_otg
[ 173.931204] usb 1-1.3.2: New USB device found, idVendor=0bda, idProduct=8176
[ 173.931222] usb 1-1.3.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 173.931236] usb 1-1.3.2: Product: 802.11n WLAN Adapter
[ 173.931248] usb 1-1.3.2: Manufacturer: Realtek
[ 173.931261] usb 1-1.3.2: SerialNumber: 00e04c000001
But it is not exactly disconnected. Guess there is some issue with the USB driver.