If you buy the premium report it can absolutely save you from buying a lemon. I was recently interested in a mercedes e class convertible that appeared to have minor rear damage that had been repaired - The car had been written off with substantial undercarriage damage, the seller was selling it without the up to date VR5 so it appeared to be a clean car. Compared to the cost of making a mistake, these reports are excellent value. Although I believe every seller should be obliged to provide such a report before they offer a car for sale, the seller pays once for a report that many can see, currently every potential buyer has to pay multiple times before they find a car they can trust!