I was assuming the OP meant the Audi R8 race car (Playstation team Oreca), and not the Audi R8 LMS (Team Playstation). Very confusing. I probably have the names wrong myself.
If it's between the LMP cars it's a wash. The Bentley is nice but so is the R8. I'd go with the one with lower miles for now.
If the R8 is the GT car then it's very overpriced and you win one from the Ring. Only worth buying for the collection or because you love R8s or like the livery - or have plenty of cash to spare. Still a great car, it just sells for three times its value.