While remote desktop access is easier to get up and running with the Google+ version, it also falls short in a few ways. The biggest problem is that you can't maximize the support window to go full screen. Instead, the desktop session is limited to the size of the main Hangout video display window. That makes it nearly impossible to see what's going on with the remote PC's desktop since the working area is so small.
Taking the Hangout to full screen by tapping F11 helped a little bit, but it's still not as good as having the remote desktop go full screen or at least nearly full screen, as you can with the Chrome extension. Perhaps if you were using a larger monitor, this limitation would not be such a big deal, but trying to get support done using a 12.5-inch display was difficult.
Remote Desktop also puts a small cancellation window at the top of the each user's screen so either person can end the remote session at any time. The problem, however, is users doing the support can't move their window. That meant the window on my PC often got in the way, reducing the working area even further. Entering a URL into Chrome, for example, was often blocked by the cancellation window.
I also found Remote Desktop in Hangouts to be much slower and less responsive compared to the browser extension. That may have been caused by connection issues or my test equipment, but I would caution you not to expect a zippy response with Remote Desktop inside Hangouts.
That said, adding a support feature to Google+ Hangouts is a nice addition that can come in handy in a pinch. Right now, it is best reserved for fixing quick problems like updating Windows or installing software. If you need to do something more intensive like analyze connection issues, configure a VPN, or do a hands-on training session with Windows 8, you're better off using the Remote Desktop extension instead of Hangouts.
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