REO Speedwagon - my first rock concert/Valparaiso University GymREO Speedwagon
The Doobie Brothers
Blue Oyster Cult
Yes (in a round about way)
STYX (they were a Grand Illusion)
There's more....
I will say though that these bands bring about memories of my high school days. Not so much that I can't stand them but my musical tastes have evolved since then.
The Doobie Brothers - seen multiple times
Blue Oyster Cult - Chicago & Headquarters in Elkhart
Yes (in a round about way) - Chicago twice, once in the round row 12 floor
STYX (they were a Grand Illusion) - Probably seen 6 times with the last time at Notre Dame with Rush
I still enjoy them all