It gives you the upper hand in close combat, as you hit stealth + nano the moment frequencies are louder, giving you most of the time an easy kill.
I've tried Covert Ops level 3 and it svcks so much compared to this
Also cloak tracker svcks to proximity alarm
IMO cloak tracker is even worse than not having it, as I'm consufed every time by those sparks
Radar Jammer is an inverse proximity alarm, you are indicating to your enemy you are next to him L O L
Tracker also svcks to proximity alarm
so, IMHO proximity alarm >>>> radar jammer, cloak tracker, covert ops III, tracker