A Little Misdirection
The Hologram is one of the earliest and least expensive armor abilities you can unlock in the game, but it has a multitude of uses for savvy players. If you're worried about getting ambushed at the end of a long corridor, just send your proxy on a death march and watch for the bullets. Most players shoot first and ask questions later, giving you a clear indication of the areas most definitely not considered safe.
If you're feeling a little more crafty, you can try this more advanced maneuver. Find yourself a nice wall and have your doppelganger walk straight into it. The projection will immediately stop and just stand there until it's out of power. Passersby looking to sweep in for an easy kill will get surprised when you sneak up behind them and turn the tables. It's a double-counter-sneak-attack!