I have been a CR subscriber and filled-out the annual survey each year for more years/decades than I care to remember. I think one can be rely on the CR survey results for vehicles that are rated high, with few problems, because the absence of a problem requires no explanation. For vehicles that are rated low by CR due to reported problems, the CR survey results are not reliable because the CR survey does not ask for or quantify a very important variable, the cost to the car owner to repair the problem. If repair cost was included in the survey results, one could make a better judgement on the impact of the problem(s) to the car owner. Another important variable would be vehicle downtime. The 2010 Prius rating is a good example of this defective survey methodology. It is rated "average" overall based on a single brake (non)problem for which the repair cost to car owner was $0.00 and the downtime was approximately 1 hour.