Crack Shot and Juke have the same goal -- reduce enemy evades -- but they do it in different ways.
Juke has exactly one advantage over Crack Shot: you can use it more than once.
Juke also has some disadvantages:
- It costs 1 more point
- You need an evade token (at the time you attack)
- The defender can negate it by spending focus
So, Juke is best when:
- You want spend an action on evade anyway (or have some other way to get a token)
- You have high PS so you can attack before using your evade on defense
- The defender is unlikely to have focus available
Omega Leader is the perfect example. You have Comm Relay to make an evade token available, reasonably high PS, and his pilot ability prevents the defender from using focus. Almost as good as permanent Crack Shot.
Where else is Juke a good choice? Howlrunner seems like a possibility -- she usually wants to be defensive anyway, and she has good PS. But if she has the only Juke in a list, the defender can just spend focus. Plus, she often doesn't live long enough to get many uses out of it. The Inquisitor has good PS and free evades, but his dial makes it hard to turn down PTL. Vader might be a possibility.
Juke is a solid EPT, but it seems tricky to consistently meet all the requirements. If it only comes together and gets an extra damage through once per game, you'd be better off with Crack Shot. Juke's effectiveness will also depend on the meta -- the higher PS the meta is, the more likely you are to lose your evade tokens before attacking.