I saw Plant live on the Now and Zen tour. Great show, but the opening act stunk (Mission UK). Wouldn’t have minded so much, but the other two opening acts (on the other two legs of the tour) were Cheap Trick and the late, great SRV. I definitely got the worst of the bunch there!
It’s interesting how some opening acts are paired with headliners. I saw Eric Clapton in 1988 and the opening act was Buckwheat Zydeco, who played through 40 minutes of booing. It was worth it for that Clapton concert, though...he had Mark Knopfler, Phil Collins and Nathan East in the band.