Like anything, it all depends on the person. You gotta experiment and see what works.
For me personally, I don't really find any value in them. That's ME! Some people love them. I do agree that most people out there need more upper/middle chest development but of course love to do flat bench cause they think benching 375lbs once means a damn thing unless your a PLer.
To me, most guy's problems in development is a direct result of EGO. I don't give advice, nor talk to people in the gym at all. But a few years back a young guy asked me why his legs wouldn't grow. He said "I'm up to 405lbs for 10 reps". I told him to let me see him squat. Of course, it was one of those gay ass quarter squats.
I of course told him he was doing it all wrong. He called bullshit. I said he couldn't do 10 reps with 135lbs. He bet me his paycheck. I put it on there for him and asked him to squat and not come out of the hole until i told him to. Long story long... 3 reps later 1 plate a side buried his skinny ass and he was nearly in tears.
If guys would leave EGO at the door, and just stuck to the basics. Squats, deads and bench, FOOD and rest... they would be amazed by how much they grew. Guys just think big numbers and single reps mean something when it comes to muscle development (again, not talking PLing here).
That's why the first question outta anyone's mouth when they see a big guy is "How much you bench?"