This card alone will make many Jinteki players cry. When installed, it can shield you from the Snare!, from advanced Project Junebug or net damage portion of Fetal AI. In critical situation it can be the most efficient tool to break past that pesky Komainu + The Twins combo.
It can break such scary ICE as Janus 1.0, Flare or Shinobi for mere 3 . What's not to love?
It is not as universal as Faerie, which can be used to break any sentries, but can break AP ICE, which means Merlin (codegate) or Wall of Thorns (barrier).
It's one-off, so you will want as many recursion as you can fit in your deck to make it available whenever you want. That means Clone Chip, Test Run and Self-modifying Code. That means you will only need one copy of Deus Ex in your deck, and most probably, you will want to play Shaper to have all the tutoring cards it needs. You will probably bring his anti-destroyer brother Sharpshooter along.
Ah, the sweet joy of playing Test Run from the three Prepaid VoicePAD to once again install Deus Ex for free.
But remember! If it's not installed, and you are about to get fried by Snare, there is no window for bringing it back with Clone Chip and then using it. Don't be greedy and install it before accessing any risky server.