A nag every 5 minutes to do so, lags and slow startup time due to all the stuff running in the background and, to top it off, horrible settings menus as the actual picture is not the main focus.
My Vizio M55-E0 has a noticeably (much, much) slower UI if it's not connected to the internet, though it's probably just poor design rather than an intentional thing. Definitely never buying another Vizio, though.
Connect your media pc to it and fully control your tv software.