The long version

Launch year turned the GT4 RS into an allocation flip, six-figure markups changing hands before delivery mileage hit triple digits. That premium has been bleeding off every year since, and as the speculators cash out, the cars left in the pool skew toward people who actually book track days instead of storage units. It wears Screamer for the shared GT3 engine and Track Rat because that is genuinely where these get used once the flippers move on to the next allocation game. Involvement is about as high as the index goes; used-market churn is the only thing holding the score back.