hi10p or hi444p?

[darkslayer00]

i was thinking was ith good for compression, pc efficiency, keeping the same color and brightness

[MichaelRow]

afaik, It's better to keep YUV444P with higher quantizer rather than downsample to YUV420P with lower quantizer, as for efficiency, it doesn't make much difference on my computer.
ScreenShot:
YUV444P10 (https://drive.google.com/file/d/0B3qFoec7GpBxSWxHN3lZOVVOWWc/edit)
YUV420P10 (https://drive.google.com/file/d/0B3qFoec7GpBxeTViUk83Mzd6bkk/edit)
You can see this thread (http://forum.doom9.org/showthread.php?p=1619723#post1619723) for more information;).

[Asmodian]

There is usually no reason to stick to 4:4:4 8 bit, better to go all the way to 4:4:4 10 bit as MichaelRow suggested. Of course if your source is already 4:2:0 4:4:4 is not helpful.