PRL and 27WON are both great. Don't forget PRL's latest release for this platform, their Cobra intake.
https://www.twostepperformance.com/products/prl-motorsports-cobra-cold-air-intake-for-2022-honda-civic-1-5t-fe1-fl1
In the real world this is a pretty silly take. Looking back at the 10th gen Civic platform the step up to the Si from the 6MT Sport turbo model was as much about the LSD as any of the other performance improvements. The same thing carries over here, especially if you are thinking about tuning...
Zero correlation between fuel and wastegate actuator rattle.
Regardless, the rattle is "normal" and not something anyone will be able to address for you. In time you will learn to ignore it. :)
Mine arrived - broken. The "bottom floor" of the car broke, likely due to too much stress from where it was attached to the display box. I'm sure HRC will replace it for me, we will see.
To play devil's advocate here, I recently saw someone who's track day was ruined (hundreds of dollars gone and a day wasted) by a failed OEM expansion tank. No doubt that Honda/Acura should "fix it for good" - but sometimes it makes more sense to take care of things yourself.
For your application I'd recommend the option from PRL. HKS and PWR both make nice intercoolers as well but there would be no reason to expect a difference in performance for your use case.
You have to swap the gauge cluster, radio, and maybe some other stuff. It's doable, yes. But not fully functional and unfortunately a lot more work than just swapping one module.
You’ll find lots of debate on this and no guarantees either direction. I’d say that tuning is no more likely to void your warranty than any other bolt on. Honda’s favorite way to void a warranty seems to be stored over rev codes.