Roku 3 or 4? I don't have a 4k television. Not sure if the 4 is worth the extra cash, seems to be geared towards people with 4k televisions. Any opinions? I really need a device that can play the mkv / avi files I have, and it would be nice to be able to watch NFL / UFC (and emmys /stuff line that for the wife). I appreciate any input, I'm new to this.