To have designed this piece I think IAG had to make some interesting engineering decisions. I’ve dropped them a star because they didn’t include a new mounting bracket for the main wiring harness. I have questions as to the possibility of wear on those harness components.
Also, for 2020 WRX’s I recommend moving the bracket down 1 extra hole over the instruction to clear the metal lip under the weather stripping. I also don’t like the included coolant clip that mounts to the turbo coolant line. I’d encourage you to purchase a stainless steel hose clamp. I’d only recommend this if you’re upgrading to a metal turbo inlet housing as it will form a better seal. If you do a crew type clamp with the plastic housing you run the risk of over or under tightening. If you under tighten, it will leak. If you will crack that plastic polymer turbo inlet.
All in all, I recommend some form of catch can, or AOS for the FA20DIT. You decide your comfort level and product. I think this is a great product with several small issues that can be resolved. One of those fixes is adding a metal turbo inlet, I decided on the Cobb piece, so I’ve included a picture of it.