10 seconds is a lifetime in combat. Make it 5.
Also preferrably works only next to obstacles, like ghost. Being invisible in the middle of nowhere is pretty dumb. That gives the receiving end a hint where the assailant might be. Could be low level perk.
If you want to make enemies, try to change something.
This perk seems interesting but according to description it will be mostly for shortrange sneakers (bursters, throwers...) and proxy scouts. Real sniper build is very perk and skill tight to accomodate any sneak skill or extra perk and dont need this. Anyone else but other 56 hex snipers just dont see him cause he is out of their view range.