We usually drive to Buffalo the night before (it's about a 2.5-3 hour drive for us). Stayed at Millenium hotel for $120 for the night, includes your parking up to 14 days and they have a free shuttle to and from the airport.
Border traffic depends on time of day, Thursday night shouldn't be too bad depending on what time. We have our Nexus cards, so we can get through pretty quick. Great thing is once you cross the border, you don't have to go through the insane customs line at the Buffalo airport like at Pearson.