are those clear protectors on the side skirt and quarter panel useful?

i have an ivory pearl and it shows black lines on the edges on the protectors. its impossible to clean and im considering removing them.

has the protectors ever saved anyone from scratches?

 

I have the IP color as well and those clear protectors have saved my paint.

I also have the clear bra made of the same material on the front and it has saved the paint as well. I agree that the edges are hard to keep clean but I'd rather have a little dirt than a paint chip.

 

I have that black line too..i really dont know how to clean it. I checked up on the parts list and it goes for like $11 dollars each side. I guess if it ever gets bad enough i'll just replace it

 

My G is black and I have a white line along that line from when I clayed the car.