So. We've been going nuts about discussing this one way or another.
However, I want to throw some things into the discussion that I don't see mentioned often enough.
Item the First: This modification can only be used on ships with both Missile and Torpedo slots.
In other words, Bombers, Punishers, K-Wings, and the Slave-1. Only.
Of these, only Bombers are cheap enough to be used for an actual Alpha-Strike list.
The Alpha Strike relies on spending the ordnance in one explosive burst, removing key elements of the enemy fleet before they can be effective, and then basically operating as a Swarm. Being that this typically happens on the first round of combat, it was named for the first letter of the Greek alphabet.
Item the Second: Target Lock is the best possible action to use outside of combat.
If you're modifying your attacks with your actions, the extra defense from Focus is generally worth more than the carry-over between rounds.
Bombers and Punishers both come with actions that let them acquire shots they might otherwise have held out of arc, or actions that let them dodge, which are superior to either.
I have often espoused TL as an action with an incredibly narrow space of use... and this upgrade blows that wide open, giving you an action that is useful when no other action is viable.
Ultimately, I fully expect a Bomber, Punisher, K-Wing, or Firespray with this equipped to out-joust a mirror-match without.
Question then becomes whether its better than Tie mk.II, Autothrusters, Advanced SLAM, or Engine Upgrades, respectively.
Late revelation: LRS is sliiiiightly better on low PS ships. That is to say, when you lose your TL on one ship, a low PS ship is likelier to be able to get the Target Lock on the round that TL is spent in combat.
It's a very minor window wherein that matters, though if I'm right and Expert Handling comes into the metagame, it could definitely come up