Short description of error
I've done some width cropping using native option, Transform strip and Metastrip. Quality is different.
(Also didn't understand why native cropper needs to chop off 160 pixels instead of 128 for transform and metastrip, because original width is 1280, so (1280-1024)/2 sides = 128)
Exact steps for others to reproduce the error
Render three times: only Transform strip, only Metastrip and only lowest strip.
There is .blend file, original vid and 3 rendered versions: