I, like most people I know, assumed that TL was better when attacking than focus. But looking at the numbers, that is not really the case.

The attack die hit 1/2 the time. Rerolling all the misses gives you a 75% chance to hit per die.

Converting all the eyeballs to hits also gives you a 75% chance to hit per die.

So, why would you limit yourself to 1 target (via target lock) instead of being able to shoot any target, or even improve your chance to evade, with the focus token?

The obvious answer is that TL carries over from 1 turn to the next and an unused focus token is lost. If you know you will not attack or be attacked this turn (because of positioning), you may as well get the TL. Otherwise, the focus seems to be the better choice.

Caveat: TL grants a slightly higher chance to get a Critical hit. Also, TL allows you to use certain actions that a focus does not.

If you do not need the TL, it sticks around. I almost never take Focus anymore on X-Wings. A-Wing's get Focus + Evade every turnb, or just focus. Y-Wings gets TL every turn because they carry ion cannons.

Firing off missiles or torpedos often require target locks.

When you need to spend a focus token to activate your brand new shiny blaster turret on your trusty Y wing. An earlier target lock is your best friend.

Aside from the obvious "save the TL and use it with focus later", TL is more versatile when attacking - of you roll 1 hit and 2 blanks, that focus token doesn't help one bit, but if you roll eyes with a TL you can still reroll them along with blanks for a chance to hit.

The only time I'd take Focus over Target Lock is when I know I'm going to receive a lot of attacks on that turn. As Halfbeard said, a TL allows you to change blank results to hits too, or criticals possibly, which is more than what a focus can do.

With TL you have a chance of converting more of your results to hits and crits. The only thing you're loosing is the assurance of changing focus results to hits, and not having the token available for when you're on the evasive.

X-Wings with Target lock I feel is the most powerful and consistant combination in the game.

TL gives a 50% increase in the chance to crit (assuming you're not rerolling hits to try and turn them into crits), which can be important for pilots like Maarek and Kath who have special abilities dependent on crits (actual odds are 18.75% per die, instead of 12.5% per die). If you're crazy and reroll hits to try and get crits, the odds come out to 23.4% per die. Also Focus + TL gives a 15.6% per die to crit, if you don't reroll Eyes.