Pros
Excellent benefits. There is ample opportunity to make money if you do not mind working 6 days/week at all hours. Leaving someone's home and getting a teary hug from them because you have made them feel safer is an awesome emotional boost and makes you feel good about your job. ADT is the oldest security company in the US, has lots of government contracts, excellent equipment, and is a very recognizable name. If your territory is a large city that has a lot of suburbs, you can do very well here.
Cons
ADT dealers can undersell a direct ADT employee and steal jobs out from under you (even though this is not supposed to happen, or you are supposed to get reimbursed if it does). Installations - at least from my office - took weeks to be installed. The installation department consistently screwed up my jobs, the installation manager does not care at all about sales reps, the scheduling department can NOT get their crap together, there were constant over-scheduling of install technicians and jobs were canceled with no reason given. As a result of the massive disorganization, my commissions diminished by over $12K my last year there in comparison to the year before. It is my understanding that not all offices are as poorly managed, but we lost our area sales manager (who had been with the company for over 15 years) because of poor communication between departments. Management is starting to expect higher production from sales reps with less leads, resulting in longer hours.