ADT is the largest home security provider in the U.S. with the most recognizable brand. But big doesn’t make ADT best. More than 400 ADT reviews and complaints collected average out to a rating 2 out of 5, which nothing to brag about. ADT uses a network of 400 dealers around the country – some better than others -- who install and service the systems. Naturally, customer experience will vary. Top complaints point to high prices, aggressive up-selling and nickel-and-diming, poor customer service, and cancellation hassles. One miffed customer wrote, “I will never use them again, I will see to it that no one I know ever uses them again.” Granted, company reviews often skew negatively, because satisfied customers rarely need to vent. Take a look at the reviews below and see what you think.