[Swizec]

A 10kg monitor is probably better because it’s gonna feel less flimsy and wobbly any time you kick the table. Depending on how the weight reduction was achieved.

[taneq]

Any monitor that doesn't bend your desk is light enough. Even ones that do bend your desk are OK if they're a Sony Trinitron. :P

[gehwartzen]

Unless your goal is to mount it on a wall. Better/worse are really not meaningful by themselves w/o context.