It depends on the promo rates vs non-promo/cashback rate. If the promo is 0% and they offer $2000 cashback on a $50K vehicle then you'd need a 1.6% non-promo interest rate to take the $2000 and break even with 0% financing at 60 months. At the time if I took the $2K then the non-promo interest rate was 2.39% so it would've cost me $1000 more over 60 months to take the $2k. Most other options for financing were similarly between 2.2% to 3% at the time. In all cases 0% was less. If the difference is $500 or less over the course of 5 years then I say who cares? Not even worth the refinancing effort.I got offered that at 60 months or a few thousand off our VW to not use the financing. I get good about manufacturer money off the selling price of vehicle and you felt great about using like mortgage points to lower the interest rate.