Pros
I worked there for five years in what they call residential retention sales. Lots of autonomy, potential to make decent money (not great)
Cons
Managers tend to be micromanagers, overwhelming amounts of paperwork both for doing business as well as doing reports, activity logs, etc. Joke in my office was ADT = Another Dead Tree. They'll hire any one with a pulse and a car, training is negligible, and management is in constant rotation. At one point my manager changed 8 times in 10 months. In 5 years, It's a 100% commission job, so no sales = no paycheck. I had 5 different pay plans, and with each change, it got progressively worse for sales people. No sick pay, vacation pay when I was there was $35/day. So if I sell 5 units in a week at the end of the month, I could make $1000-$1500, but if I go on vacation that week instead, I get $175. Opportunity for advancement is slim, and if you do advance, your reward is basically more hours, almost all stuck behind a desk, for less money than you made when you were selling. It's a shame when at a company the size of ADT, you can be a top 5 sales person in a region (top 100 in the entire country) and not be earning 6 figures. Keep in mind my information is based on my time there, which ended in 2009. Things may have changed since then. But based on talking to the people I still know there, they haven't changed much.