The disc brakes are a sliding caliper type disc brake system. The brake systems used by Audi and Volkswagen are subjected to rigorous testing and must meet stringent DIN industry standards. The components of the brake system are designed to be compatible with one another. Aside from steel braided hydraulic brake lines, different brake pad compounds and the addition of improved cooling ducts, there is very little that can be done to improve the performance and reliability of the original equipment brakes short of upgrading the entire brake system.
When replacing or repairing the brake components, for reasons of safety and liability, use original equipment components that meet the manufacturer's standards. If the vehicle is used for sporting events or closed course competition:
There are many high performance upgrades available from reputable vendors, however their cost may not be justified unless the vehicle is to be used for competition purposes and may not be practical for street use. If an aftermarket brake system is being considered, make sure it will fit with the existing wheels and suspension components. If the vehicle is to be used for competition purposes, check the rules carefully, as some classes have specific instructions as to what can and can't be replaced or modified.
Brakes generate a great deal of heat and under severe use, could shorten the life of items such as wheel bearings or other related suspension components. Because of the heat generated by the brakes, the use of brake dust shields is not recommend. These shields mount between the wheel and the hub, blocking the flow of cooling air that is needed to dissipate the heat generated by the brakes. Airflow must be maintained through the wheel to prevent component damage, premature wear and brake fade.
There are many sources of brake pads available for today's vehicles. Brake lining materials used include carbon, metallic, and most recently, ceramic compounds. The ceramic compounds claim to create less noticeable black brake dust which along with brake squeal has been a common industry complaint since the removal of asbestos as a brake lining material. There are tradeoffs that one must consider. A brake pad that has an extended service life is usually a hard compound that may offer excellent performance and durability at the expense of increased brake rotor wear, and is more likely to emit a brake squeal noises on light braking.
Soft brake pads are less likely to squeal, but wear more quickly and may not offer the performance some drivers expect from their brakes. If deviating from the original equipment pads, seek the advice of those who have tried them. Otherwise, use original equipment brake linings. Consult your local dealer for their recommendations and by all means, NEVER compromise safety for any reason.