I feel like such an old man now. I took delivery of my i30N in April 2018, I believe it was the first i30N delivered in Queensland, Australia. It now has over 25K on the clock, I have had ZERO issues, other than some really minor stuff, so all is good in my i30N world!
Hyundai Australia have NEVER offered mudflaps for the N, I bought a set for the regular i30 and modified them to fit, but they are pathetic, and offer little or no protection.
In June 2018 I posted this "how to" on installing mud flaps.
https://n-cars.net/forums/threads/how-to-mud-flaps.926/
Me, being a cheap arse, bought the "basic" Rallyarmour flaps for about $60 AUD. (LONG before the other company came out with CUSTOM flaps cut to size with mounting fittings and 3 times the price).
The instructions on where to cut them, and how to fit them is all in the how-to, and trust me, you do not need to be a brain surgeon to fit them, most of the holes are there already, the other holes are easy to drill, and the mudflaps have been on my car for 19 months now.
The crap coming off the road is way less, I pulled them off last week to check what was sitting behind them, and it was virtually nothing, so I was really happy. So much so, I recently installed the same flaps onto my wife's Cerato GT (Forte, K3)
Yes, it does give MY car a "rally car" look, something I don't mind, and other people have noticed and liked. There is always the option to move the holes "outward" by 10 to 15mm which will pull the mudflaps "in" by 10 - 15mm, giving a LESS rally look, and offering slightly less protection. Remember I also have 8.5" rims with +44 offset, so MY wheels sit 17mm further out than the OEM wheels, the crap coming off the outside of the wheels is much more likely to hit the bodywork. Pull the holes in by 15 mm from my drill points and they will NOT look so rally inspired.
You can mount them with the logo backwards if you like it, or forward if you want a stealth look. They extend well into the wheel wheel, so the crap on the rear of the car is reduced, but I have always found the exhaust pipes create most of the crap on the back of the car, not road rubbish.
Good luck with your mudflap installation, which ever way you go. And happy to answer any questions.