Chronicle is a found footage dark superhero story entailing people being exposed to an alien artifact and gaining telekinetic powers (which they also use to make themselves fly). Rush is about people being exposed to a mysterious shaft of light in a cave and being given the supernatural ability to vibrate at an ultra-high frequency (which also allows them to move fast).

Sure they share the extremely general theme of being exposed to something and gaining a special ability, but that's been done in cinema and TV countless times. There's no "copy" here. Whether someone likes one better than the other is a matter of personal preference and opinion. I very much liked both of them, although I'm a sucker for a subversive superhero story (e.g. like Unbreakable), so Chronicle took me by surprise and became an instant favorite.

I'll add that I really miss the very creative storylines presented in most X-Files episodes. I actually like the stand-alone stories better than the underlying mythology (well, after the first couple of seasons, anyway), perfect blends of darkness and humor. Humbug is one of my favorites, along with Triangle (which possessed themes later portrayed in Christopher Smith's excellent mind-bending film Triangle, which is one of my favorites also).

Sigh. I don't like living in a world without weekly X-Files stories. I also don't like being old. Hmm. Maybe I should acquire the ability to quantum leap back into my younger self.

And now, a line from the episode Humbug (and a link to the funniest bits from the episode: https://www.youtube.com/watch?v=-vm0Gvxuvsc):

"You see I've seen the future, and the future looks... just like him." Points to Mulder, who's standing one leg on some steps, arms on hips heroically. "Imagine going through your whole life looking like that". Classic.