As far as I know, your primary problem between wireless and Cat6 would be speed/reliability. Cat6 obviously being the much faster more reliable option. In some cases when a hiccup occurs or when the streaming is requiring too much bandwidth, applications such as Netflix will bump the video quality down to a much worse picture automatically. This of course is because a lower quality picture is easier to load. This can happen with wired or wireless, just much less often with wired. Overall, most wireless connections, depending on the router and your service provider, are very reliable and typically you won't run into any problems.