They had a nice histogram, showing the range and most common price and how far off msrp it was.
I don't know how accurate it really was, and if it was accurate, someone might have "gotten to them" in later years to inflate the statistics and preserve profit margins.
But it seemed to me really valuable information for negotiating a new car purchase. The special True Car price and "services" and all that seemed like a diversion to me.
It's like some other things on the Internet - a sensible person subsists on the free "teaser" information and never ever engages in any sort of relationship.
Apart from an indication of what a fair price is, the histogram showed relative discounts between models, and there's frequently/always ones that are being disdained by the public that are very good cars and dealers are desperate to move, versus ones that are in high demand that they won't discount.