Hi, most of the 720p mkv movies I watch come in around 5Gb or above. Recently I've watched a few at around 2.7Gb, and I can't see any real difference. I have a high spec smart 50" Panasonic T.V connected to an HDMI out 1080p from my P.C. I use 720p for space saving purposes. Are these smaller files lower quality or has coding improved?