There are $10 rebate forms on 5qt jugs at Walmart. $12 after rebate for Platinum. $16 AR for Ultra.
I use aftermarket filters on my Nissan Altima. Currently use K&N (B1G1 Free ends today! at Pep Boys).
I use factory filters on my KIA Optima (Hyundai/KIA make top-notch filiters)
I was at Wally World twice last week to buy Platinum and none of the bottles had the forms. They didn't have any at the auto center desk either.