I think downscaling to 544p is useful only if youre limited at disk space or if you want to store it for a long time. There two main problems with scaling - soapy lines/artifacts on bad sources and conversion time. For example - hardsubbing 25m video with 720p takes about two minutes (NVENC...
It's better to update to 3.65 and use Enso. As for your main question - I use Movavi to convert videos. It support NVENC and Intel QuickSync for many formats, and mp4 is one of them. Also there is good support for subtitles (many converters that I've tested fucked up with SSA/ASS files). I use...
It's not the movies or games downloads that I would worry about, like breaking into networks, downloading encrypted things, spying on network traffic. I have seen so many "Top Secret" seals on files when I was a kid
I was obsessed with finding UFOs, a surprising amount of US files where stashed on computers in other countries, China back in the early 90s omg sooo much