I've been to a lot of shows. It's definitely a mixed bag for me. Lately, we've seen a lot of really bad local bands opening. A few really good ones, but a ton that have been awful. Twice for Ace Frehley, we saw a band that had a female member who did nothing. When I say nothing, I mean nothing - no tambourine, no vocals, she just kind of stood in place and sort of swayed. We saw one band open for John 5 that was so bad I asked a cop who was working security if someone had called him to report a group of people impersonating musicians. He laughed and said, "I know who you mean." A couple months ago, we saw a band that made my buddy turn to me and say, "Do you ever wonder what their friends tell them when they hear this?" And a couple years ago, we saw a band that was just a disaster from the start. The singer's guitar didn't work, so they had to get one from his rack. Which had all the guitars strapped in, and they couldn't get one out. Then he walked over to one side of the stage, got tangled up w/the bass player's mic stand, and ultimately tipped it into the crowd.
But the bad openers let me work on my sarcasm. At one show, during a bad opener, I told my buddy, "If you're nice to me the rest of the show, I'll buy you one of this band's CDs on the way out. If you're not, I'm buying you two." At another, I asked my buddy if he'd checked out the merch table after the opener. He said no. I said, "You should. That band has T-shirts for sale w/their logo for $10. They also have plain shirts for $15."
On the other hand, I've seen a lot of good openers over the years as well, some of whom became favorites of mine. My first rock show? New England opening for Kiss. I've loved them ever since. I saw the aforementioned J.D. Simo open for Ace Frehley (after the previously mentioned opener opened two shows). He was way better, and I told him so. Hannah Wicklund has become a favorite since we saw her open for Marshall Tucker. Way back on the Diver Down tour, there was a blues/soul band that opened for Van Halen. I have no idea who they were, but they were great.
My favorite opener story, though, was going to see the Who. I saw in the paper that they had a opener, and I was just in a mood that day, I guess. I complained to my wife that I didn't want to deal with an opener and maybe I should tell my buddy we'd go late. She said, "Just suck it up and go. You know you like checking out the openers." Despite marrying me, she's pretty smart. We got there, and walking to our seats we saw they had a table set up for the opener to do a meet and greet after the show. I think I snickered or shook my head. We sat down, and there's the big Who stage, and way off on one side is a carpet about 15' square, with a small guitar amp, small drum kit, and a bass amp. I said to my buddy, "This could be interesting." But in a sarcastic way (see above). Then the band comes out in these old-style suits, to an old blues recording. They gathered around the drum set and all shook hands. I just kind of rolled my eyes and said OK. Then they started to play - by the end of the first verse of the first song, I said to my buddy, "There's not a chance in hell we're walking out of here without their CD." That was Vintage Trouble, and their one of our absolute favorite bands. We've seen them so much my wife said, "Do you think they wish their groupies weren't two old fat guys?"