tai pranašesnė tik tuom, kad ant auto su 310mm stabžių diskais galima užmauti 15" ratus. o gražinamos buvo dėl juntamo mušimo per vairą stabdymo metu, t.y. dėl susikraipiusių pačių stabdžių diskų, o kad pagrinde V8, tai tikriausiai todėl, kad masė didžiausia iš visų su UFO, tai užkaisdavo greičiausiai ir susikraipydavo. o ir tie gražinimai (su keitimais į 276mm stabdžių diskus ir Girling suportus) kiek žinau buvo tik in USA
EDIT: labai trumpa ir išsami info duotu klausimu:
UFOs were designed by Audi to get the largest possible brake rotor inside a 15-inch wheel. In the late 1980s, when the car was being developed, the best high-performance tires available were 15-inchers.
UFOs are the easiest disk brake system ever for replacing the pads or rotors. Replacing caliper boots/seals is about like any other caliper.
However, there is no servicing of the caliper pin system, so if you get inordinate wear of the pins, the caliper needs to be replaced.
Rotors are expensive but last a lot longer than most other types. Pads and rotors are becoming difficult to obtain, however.
In the USofA, too many UFO drivers did too much stop-and-go driving where they left hot pads and rotors pressed together at stoplights, and warpage of the rotors occurred. Audi's solution was to "update" the front brakes of UFO-equipped cars with the inferior rotors from the URS cars of 1992-on. Those brakes work as well as the UFOs for the occasional hard stop, but using them on a track or using them on long mountain downgrades can lead to significant fading that the UFOs didn't exhibit.
A better option is to get larger wheels and add Porsche or some other performance brake system.