Hello

Welcome to the forum, find out if you had the ECU recall. If you had the recall, premium is better but you won't be able to feel the difference and may discount the whole idea of it. Either way, you need to run multiple tanks low(not empty stuck on the side of the road low). The car gets used to a fuel map of 87 and won't let you hold the 91 (KRD should be on the sticker in your glove box for 91) fuel map for more than when you get gas at the gas station. You will feel the 91 fuel map give it's initial spike after getting gas and trying to speed up to merge into traffic. Once the 87 octane proves it's not 91, it will pull back to 87 map.

For me I can't run 87 in my 13 eco 6mt. I will stall at lights and stall in the winter with T/C turned on. Dealers said it was normal and after I went 93 and NGK plug swap I was fine. Now tuned (least mechanical and safer than chips), I been liking the car even more. It has it's issues here and there but when it runs fine I'm content.

There is a headlight harness upgrade but it is mechanical install.
Fogs if you already have them, not sure besides bulb swap. If not installed it's mechanical and most likely already programed to be Plug N Play after you mechanically install the kit.