KIA did have special financing 0.9% @48mo, 1.9% @60mo, and 2.9% @72mo depending on the length of the loan, but everything the dealer told you was "required" is utter garbage BS. When I went to purchase mine, the salesman told me that, in order to receive a $1000 discount, I needed to finance with KMF and stay with KMF for at least 3 months (I think there was some BS in there). One thing I hated was that the salesman was NOT transparent about these deals; when I got to finance they were like "oh it's either the $1,000 or the lower % APR", which the salesman had said was I needed to use the lower APR through them to get the $1,000. When I bitched at the salesman he just said "you understood me wrong" even though I checked about 4 times with him reiterating to ensure there was no type of miscommunication. My wife agreed they were full of $h!t. I could have left, I suppose, but the car would have gotten snatched up before I left the dealer (there were literally two couples at the dealer waiting).
Ended up being a good deal, but it left me with a sour feeling.
So, better rate is possible, but 3.00%, from a credit union, is pretty damn good.
Good luck!