I think it's up to you, if it doesn't bother you, if you are REALLY saving and investing the money that could go to the principle, and the cashflow isn't an issue.
I had a student loan at 3% in the 2000s when ING was paying 5%+ on their interest rates and thought, "well it's stupid for me to pay extra with that interest rate". But I never saved it. Then I had a car loan at 2.99%. So then we go to buy a house and there's 500 a month tied up in low interest loans. I paid both off real quick, less money going to it.
before realizing financing is stupid I bought a new car after my last died in 2010. 2.99% again, but this time I despised thatt loan and owing money so I paid it off in 1.5 years. I'll never take a car loan out again, or borrow money, I don't even care if it's 0% loan. That's just me though.