Well, with my new to me 2018 Santa Fe, I replace everything I can, including the cabin air filter, even though there is only 10,800 miles on the vehicle. This is the OEM Hyundai filter (971333SAA0), not sure what it looks like new (pics look white), but it was a little browninsh looking and was some larger bits of stuff in it. Not bad by any means, and probably could have been in for another 10,000 miles, but just want to make sure everything is good, so out it came. I installed a Fram FreshBreeze CF11819, got it off Amazon for $9 (back to $14 now) Side by side of old and new. Figured I would give one of these a try instead of OEM. I have used various "cheap" brands in the past on other vehicles with decent results, and this Fram was actually the cheapest at the time. I am debating using some filter media I have from my home ac unit that I can cut to fit, but not sure if they would be any better or worse than this.