LOL there are no experts on bikeforums. Other than the armchair variety.

That said, on SPD-SL cleats the yellow or red plastic bits are simply wear indicators and don't affect the cleats, my personal experience with the yellow cleats is that the plastic wears off extremely quickly and the cleats themselves are good for a long, long time. I wear them until they don't seem to clip very well, and I can't actually remember how many miles or the last time I replaced them was, but it's a lot.