What is your least favorite Mayberry RFD episode and why?

I disliked all of the final season primarily because the old town of Mayberry was gone. After the second season, the studio destroyed the downtown set that had been used for both THE ANDY GRIFFITH SHOW and MAYBERRY R.F.D. The production then began to utilize the town square that would later be used in shows like THE DUKES OF HAZZARD, but it just wasn't the same.