No, but I plan to use a post of mine here as a suggestion.
Here Goes:
What would be even better is to restrict cars to players by their A-Spec level, offline and online. If you're an A-Spec Zero (0) and Bob is a B-Spec Hero (40), Bob has the right to race an X2010 and certainly not you. This will also help with the gifting issue of, say, duplicated high level cars and kiddies getting super powered cars while being an A-Spec Zero. Sure OFFLINE you can test cars higher-level-than-your-own, but can't race them to progress yourself.
Speaking of duplicated cars...
This brings me back to Pokemon, and I'll tell you why. In Pokemon, when you captured a Pokemon, it is OT/*Your Name* (Original Trainer/*Your Name*) and given a 12 digit ID (6 visible, 6 hidden). That way, two players under the same name can't share Pokemon that they can call their own without people knowing it's been traded.
NOW, back to why Pokemon is so important. I think every car earned, by ticket or purchased, should have their name inscribed as the first original owner of the car, along with a, say, 12 digit hidden ID to the car. With that, you have a completely unique car.
Now how will this solve duping? Easy. Once it is detected that two cars of the same registered name and ID are present, that car is locked/removed. Same can go for Paint Chips/Horns/Car Parts.
Why have the hidden ID if all PSN names are unique themselves? Well, if you bought two Ferrari Enzo's, they both could have two different ID's without both being locked/removed, because (Guess What?) you earned them without duplicating.