if you can make a direct CABLE connection, such as an HDMI cable, to your TV set, results will be Vastly superior to any of these ROKU or Apple-TV solutions.
An ordinary display requires upwards of 6 G bits/sec, and more typically around 9 G bits/sec for full speed, full motion Video.
Really good WiFi connections provide a data pathway up to 1 G bits/sec, far short of lossless data rates required.
Even with really good compression, picture quality will never be nearly as good as a direct cable connection. It will be especially obvious for Full-Motion Video or Full-motion gaming.