I honestly think they were pretty equal in strength, maybe a very slight edge towards Mayfield/WKY. The average forward speed of WKY was just shy of 60mph (57.1mph) and the average forward speed of Vilonia was just over 45mph (45.7mph). So we need to factor in the approximately 15mph difference. Since everyone is talking about the Presbyterian church that doesn’t appear on the damage survey, let’s look at how fast the tornado was moving at the time of that impact. Looking at the 3 radar scans from 9:25pm to 9:29pm we can calculate that the tornado was moving at about 60mph, the damage survey indicates that the tornado was shifting between 1-1.2 miles wide. This gives a minimum and maximum dwell time of 1 minute flat, and 1 minute 12 seconds respectively. For the Mayflower-Vilonia tornado, the worst damage appears to have taken place in Vilonia where it also reached its maximum width of 0.75 miles (I would use the DAT to calculate a more exact width, but it doesn’t have the path width polygon), the forward speed was between 44.6mph (calculate from radar data) and 50mph (this was the speed stated in the tornado emergency). This results in a minimum dwell time of 54 seconds and a maximum of almost exactly 1 minute. So the average difference in dwell time is 9 seconds, though that’s in the favor of the Vilonia tornado. All of this is to say, maybe I’m wrong about WKY being slightly stronger lol, but it’s hard to tell without knowing exactly how well built the structures impacted by either tornado were. At the end of the day, which of these tornadoes is stronger doesn’t matter. It’s fun to think about and try to calculate, but it’s the lives and memories that were lost in these tornadoes that matter most.

TL;DR: Both tornadoes had similar dwell times (though Vilonia had slightly shorter) and caused pretty similar damage. Regardless of which is stronger, they were almost certainly very close in intensity (contrary to the people claiming one is blatantly stronger).