TRIGGER WARNING: This will upset MANY people.
I WAS experimenting with various forms of these. I am about 70% red/green colourblind so to me, these balls stand out yellow, not fluoro yellow, but yellow nonetheless.
This colourblindness also affects my brain's interpretation of blue/purple and I have trouble distinguishing between browns and greens if they are in the distance etc, making golf one sunnuva in summer here when the course is cooked.
To non CB people these are a dirty yellow (so I am told) and are very hard to see on the course. So while I can find my own balls easier than a white-only ball using a marker, my playing partners helping me look for a wayward ball cannot, and I found I was losing more shots by not having that extra help when the chips were down.
And although this was done with "permanent marker" it was invaluable in telling me if I was hitting off the toe. I'd actually recommend it to anyone to use for a round or for practice and have a look after each shot what shot shape happened after different strikes. Yes, it puts some muck on your club face, but yes it rubs off quite easily, and I may be colourblind but I'm not certainly less worried about the temporary aesthetic assault on my clubs than if I'm drinking my playing partners' free beer at the end of a winning round.
Anyway I've learned to stick to fluoro yellow so I can see them and my buddies can too. And they've stopped feeling like vomiting and their OCD has calmed down big time since they had to stop looking at them on the tee and green.