Why should I pick Kog'Maw or Twitch over Jinx?

I'm starting to feel like both of them just can't compare to her. They both have severely worse early games, Kog'Maw is a lot worse than both of them come mid game, and Jinx is overall a lot safer in terms of teamfights and risk-reward. Jinx has a similar range steroid, but it has no downtime whatsoever -- most AD Kog builds (assuming no CDR) have 9 seconds where theirs is down and Kog'Maw only has 10 more range than her, and Twitch only has his for 7 seconds and it's his ultimate. Not to mention hers hits in an AoE circle as opposed to Twitch's straight line and Kog'Maw's needing a Runaan's for a similar effect. Another huge advantage she's got over the two of them is more reliable escapes and disengage, especially if she scores a kill or an assist, where she suddenly turbo-charges to get multi-kills or gets out of dodge if it's going bad.

Jinx also has a higher attack speed steroid than both of them, and with no downtime to it as compared to Twitch. Twitch's is attached to his stealth, which, while it makes him absolutely astounding at flanks and surprise attacks, also leaves him incredibly vulnerable if he gets caught or it's on cooldown. She's got better slows than both of them on a MUCH lower cooldown, she has hard CC which neither of them have, arguably better scaling on her abilities, and roughly something the same as Twitch gets on his ultimate on her Fishbones, which is a normal ability. I could say that Kog'Maw melts you a lot faster if you're a tank, but I don't recall being a bad item on Jinx, not to mention she's got pretty devastating crits.

The only reason I'd see Kog'Maw being a better choice right now is because he's still got much better poke and siege come late game, but Jinx certainly isn't bad at it either with her range buff. Twitch is my favorite ADC right up with but honestly, laning with him is so miserable that it's incredibly discouraging to pick him up again.

So I'm going to come to the forums and ask, why should I play either of these two over Jinx, and why I shouldn't buy her instead of a champion I'm more inclined to enjoy with the IP I've been building up just so I have a strong ADC for ranked play?