Charts comparing the different models of Roomba vacuum cleaners are found at TopProductComparisons.com and OneFamilysBlog.com, as of 2015. Both websites feature charts that compare features such as price, weight and warranty of Roomba models.
A comparison chart of Roomba vacuum cleaners is found on TopProductComparisons.com by clicking Compare iRobot Roomba near the middle of the home page. The comparison chart is displayed on the next page along with detailed descriptions of the differences between models.
A comparison chart of Roomba vacuum cleaners is found on OneFamilysBlog.com by clicking Roomba 800, 700, 600 & 500 Series Comparison/Review under the Consumer Products heading. The chart is displayed on the next page. The page also details the similarities and differences of the different models.