Hi Hodad66, yes you can do this, we just took delivery on a Niro L trim (canadian base model) with the standard radio in it. I was ripping my wife's CD,s to USB flash drive, I ripped the original CD as highest quality Flac (8) to archive I was planning to burn some MP3s at 320. Thats the highest file compatibility according to the Kia Entertainment Manual. Anyway I copied some flacs and MP3s over to test in my daughters Mazda 3. Hers is high end radio and I wanted to see if I could notice a difference. There was a noticeable better sound with the Flac files.
Then I tried in Niro and it played both types of files, was very surprised the Stock radio played the Flacs anyway that saved me a ton of time as I don't have to convert them all to MP3 . Obviously the base speakers are not as good as the higher trim models with the Harmon system. But for us its fine.
I also test drove the highest trim and that system was very very good as a comparison.