R&G makes rear spindle sliders for the S3:
and front fork protectors for the Daytona 955i (as well as the 05+ S3):
I contacted R&G and asked if the fork protector would fit the S3 (reasoning that the Daytona and 02-04 S3 share a front end--
am I wrong here?) and the response was that the fork protectors for the Daytona only fit the Daytona. Can anyone here confirm that the Daytona front wheel and fork is the same part as the 02-04 S3 front wheel and fork?
Skyking also has a rear spindle slider for the S3:
made out of anodized aluminum.