Pros
Job security is definitely a pro, if you are able to handle difficult customers and provide great customer service no matter what, you are in good shape. Management is usually always there to help, worst case scenario you can always call another store for advise.
Cons
Simply put, a lot of stress. High turn over, people will not take to amount of responsibility for what it pays. Once they get hired most of them can't handle the over load of responsibility and customer harassment that comes with the position. Compensation is not good enough to keep good employees from seeking better paying jobs. Must learn most systems in the store that involves other departments (not really a con, knowledge is power) but you are always the backup and the other departments will tend to hand over their issues for the Service Desk to fix especially when it involves appliance issues.