Do your alloys have a diamond cut finish. If yes, then some types of rim protectors aren’t recommended for use on diamond cut alloys as dirt and grit can get between the rim protector and wheel with the potential to damage the wheel’s diamond cut finish. When this happens, white worm corrosion can occur under the rim protector and if left, can spread over the diamond cut face of the wheel. Refurbishing a diamond cut alloy to remove white worm corrosion costs in the region of £120 - £140.
Additionally, some of these types of rim protectors (e.g. Alloy Gators) are attached to the wheel with a fair degree of force (e.g. by hammering them on to the wheel with a ‘soft’ hammer), with a risk of damaging the protective lacquered surface over the diamond cut finish on the wheel. Damage to the lacquered surface more often than not results in the onset of white worm corrosion. They rim protectors in the picture you’ve posted look as if they’re attached by a self adhesive backing strip rather than by hammering on. If so, then attaching them shouldn’t damage the lacquered surface on the wheel.
There have been instances of the Alloy Gator type rim protectors coming loose, and causing damage to car body panels as the loose end of the rim protector hits the car bodywork with force with each revolution of the car’s wheels. The type of damage they can cause can be seen in the picture towards the bottom of the page in the discussion topic on Pistonheads forum at the link below;
I personally don’t like rim protectors and wouldn’t fit them to my car for the reasons stated above.