Make the drive once or twice a year, we flew down in September, and cost us about $900 for the two of us, plus we had to cab it too the hotel for the wedding. Hated not having a car in Dallas.
Its not a bad drive at all, we take I-35 down and over to St. Jo, jump on I-29 and that takes you all the way to I-70 and the Kansas turnpike. Oklahoma City to Norman can be a pain if you hit it at the wrong time, but no too bad. Dallas is a pain in the ass from Denton all the way downtown.
We can drive our Camary down and back for a couple hundred in gas and food at most. Quickest I have made it is 10 hours, but that was leaving on a Sunday morning from Dallas and flew out of town. Our flight was out of KC, whole deal was 7 to 8 hours. So, we saved maybe 3 to 4 hours tops. If we had more time, we would have driven it, like we plan to do at Easter.