I started concerts around 1970.
Best ever was Eric Clapton when he did the first set all acoustic and started it off solo. Later Clapton was joined by Billy Preston on the big Wurlitzer, really great show. also saw Jethro Tull, ZZ Top, (the first)AC/DC, Van Halen, Ted Nugent, Earth Wind and Fire, REO Speedwagon, Charlie Daniels band, Edgar Winter, Jimmy Buffet, Nitty Gritty Dirt Band, Willie Nelson, etc... Dan Fogelberg was great.
Worst was Jery Jeff Walker. He was so drunk he kept falling off his barstool and couldn't perform at all, he got boo'd off the stage and the backup band came back on and were better anyway.