ADC Jinx or Corki
So I can't decide should I get
or 
So I can't decide should I get
or 
Both are pretty solid ADC's. Corki has a bigger mid game power spike compared to Jinx. But Jinx scales into the late game like a monster. Anyone would be more scared of an out of control fed Jinx than they would a Corki, but Corki has a pretty strong laning phase as well.
Jinx though is possibly getting some nerfs to her Q's attack speed stacks that will make her mid game slightly weaker so if you want that mid game dominance Corki is a good bet over Jinx. I personally really like Jinx though all things considered.
Corki is just really safe and good in pretty much any meta.
Jinx suffers a bit if a lot of assassins are running around, but she's still good.
Corki is a caster ADC similar to Varus and Lucian, where as Jinx is similar to old style Trist or Kog, I.E. traditional hyper carries. They can both carry: Corki will have an easier time getting to the end game, Jinx, given the same amount of gold, will carry harder.
So pick your poison. You can do well with either.
Corki has a godlike powerspike mid game when he completes
+
, maxes his Q at level 9 and ranks up his ult at level 11. He is the strongest ADC champion around the 20 minute mark in the game. This is offset by an average laning phase, and a subpar end game since he lacks attack speed steroids.
I love Corki, but I prefer playing him mid lane, so you can have extra levels from solo lane exp, and your team can run an ADC with a strong lane phase or one that hyperscales late game. As a mid laner you have waveclear/ poke/ burst damage, you just don't have CC like the average mid lane, but you have consistently high auto attack damage unlike them. You can abuse AP mids with your ranged AD atttacks if you dodge their skillshots. When you solo lane you can grab
+ potions and just trade aggressively with your auto attacks and ap mids might have a hard time dealing with your total hp with their limited mana pool.
And believe it or not Corki can be adaptable and diverge into an ap poke build. It's mostly for poking at a distance instead tho. It will not kill squishy carries as quickly as critical strikes would. The AP build looks something like this:
>
>
/
> 
Meanwhile Jinx is a very fragile hypercarry that goes out of control in some circumstances, and demolishes enemies that make mistakes or when you just have a good team to surround yourself with. I dislike Jinx because she is basically just a glass turret that relies on teammates but she is very popular and statistically overpowered right now.