Why let your alloy wheels look like this. This damage has been caused by the use of improper cleaning products that has corroded the metal and damaged the wheel. Even damage like this can be corrected.
This is the same wheel after being refurbished. 
  This is an example of less servere damaged caused by kerbing the wheel. Many repairs will use some sort of filler to fill the damage. This is bad practice as in some cases fillers will only chip / fall out again.
 Afer a few hours the wheel looks like new again.