Pros
Worked with T-mobile for 5 years and there are many others who stayed with the comapny for even longer. They provide good pay for the position, a fair commission structure, lots of support from management, and a GREAT work life balance. There is TONS of PTO time available and it was not uncommon to see reps take vacation for 3 weeks or a month at a time, plus they supplement your commission while you're on vacation. In the stores where I worked, the competition among reps was alway friendly and there was no stealing customers from each other, but I've heard of that happening at other locations. If you work hard, you will be promoted. They offer good service and fair pricing to customers (comparatively) so the products are not hard to sell at all. Overall, great company, they truly live their corporate vales. "I am T-mobile, count on me"
Cons
The wireles industry changes very frequesntly, so there will ALWAYS be new phones, new services, new plans and new everything to keep up with. Also, there is always the chance that you'll get a bad manager, or greedy co-workers who steal your sales, but in general my personal experience was very good. They have a "black-out" period around the holidays where no one can take vacation...but my birthday falls during this period and I was always able to take a birthday vacation, but that's because my managers were all really cool.