I've been know to use yellow Srixon Z stars and they are easier to follow in flight but once they are on the ground they're no easier or harder to find in the rough
No idea why a yellow one feels harder than a white to some people, as the only difference is the colouring they use for the cover. Rather than using the white dye they use a yellow variant, is that really going to change the performance of the ball ? Must surely be psychological ?!?
Once the daisy's are up in the semi rough or when there's a heavy dew or frost yellow balls are much easier to see. I also find them much easier to track through the air especially when the light is just going.
In good conditions I usually use white however I'm more than happy to use yellow
I have poor eyes and do like the ease of following them in murky conditions but really struggle with looking in the rough. I've certainly never found them harder than white counter parts. I actually like them on the greens too and find I do putt well with yellow models. I'm not sure I'd ever make the switch fully though
I would say the colour of the rough itself makes it earlier/harder to view a yellow ball. If the grass is green and lush compared to burnt out the difference between yellow and white can be quite startling.