Pros
I agree with reviews of T-Mobile as being diverse and relaxed in terms of the call center work atmosphere. I also find that a positive attitude will be reflected in the day to day work operations. I don't find it difficult to stay abreast of new developments in policy and procedure in the sense that if you are quick on the uptake and have an accurate concept of the pace of progress you should be able to keep up. The benefits cannot be beat, not to mention the benefit of a steady paycheck nowadays. The pay is competitive, although not necessarily reflective of the skill/intelligence level or even the dependability of the employee.
Cons
Sadly, one of the downsides of my position is the attitude of the customers towards customer service representatives, and the naivety with which they handle their accounts and affairs. The other major challenge is the "loyalty at all costs" mentality that the middle management visits upon the front line employees. I doubt if this is a condition that is any different from any other major wireless/retail corporation, but it can make you feel like they are dangling your job in front of you like a pork chop and you have no alternative but to throw your personal life/family commitments/mental or physical health under the bus in order to keep your job and (potentially) receive all of the benefits that they promise.