Well if it is the covers yellowing I am glad I am part the incandescent fan club Spending all that money on LEDs and boards to cover up issues. now this. Geesh

Yes I don't think suppliers names and brands mean much of anything they are all made in china.

I don't understand the need to be so hard up on LEDs

let's think about this. Not that I have many LEDs I don't.

But from a quick flippers point of view.

If I led the game in will run me one hundred dollars or less and not much time.
Now really what he is doing is taking strain off failing circuits making bad lamp sockets seem OK Headers that may be getting hot will not so no need to do as much work. Or the fact that he can't do the work anyhow.
Plus it is now Almost (NOT to me) an upgrade. So due to the fact it is so nice and pretty I can figure an extra 200 in profit.
As everyone know LEDs are wonderful and you will never have to lift your pf again a bs selling point.
That to me is actually a bad thing as if I open machine up regularly to change a bulb. I do a visual for other things like flippers loose screws ect. Which should be done anyway but aren't as no need to all lamps are good.

But back to original post if LEDs don't give off uv and the domes are not changing color with age due to heat. Than it must so and so's cheap ass plastic domes. Or a single incident manufacturing defect.

Well I am still not buying it. I really want to like LEDs but I can't.
And the pro led guys keep putting that square peg into the round hole no matter what the cost.
Don't forget to buy your OCD board and modify those other circuits for flashers

What bothers me are a lot of the videos on unsafe household led bulbs that can kill you!
My son brought some led bulbs as he too has the hardon for LEDs
I could not believe the size of the heat sink for a 40w equivalent bulb it is actually straining the hell out of the holder due to weight. I hate that they are forcing the extinction of regular incandescent.

That is weird. So those three were all the same at one time.
I would experiment. And try to change just the caps from 9 and 3.
Then take another pic.
In all honesty though if you had regular bulbs and replaced one you would likely see just as much difference as different filiment ages.