I have not noticed a huge difference between oils in our ownership of wife's 2013 elantra GT with the nu 1.8. Now with 167,000mi.
The valvoline maxlife blend 5w-30 and champ xl filter in it now runs a bit quieter and quiets down more quickly than the QSFS 5w-20 and champ non-xl filter that was in it. But is that the fresh oil, viscosity, or better filter I really can't say.
I do think 5w-30 runs quieter overall than 20wt, but only a little bit. I have typically run 30wt in the summers and 20wt in the winter and it has worked fine on both.