Pros
They pay well for the work you get to do (tech support) but you'll be kept on a tight leash by the dozens of managers they employ which have no clue what the work you do actually entails.
Cons
A lot. 6 day shifts (either day or evening) with only short notice will put a strain on your social life. Don't expect your manager to care as he'll be too busy making reports (which is all they actually do - it's all about "stats") for the manager above him which in turn will do the same for the manager above him. So many layers of managers that you start to wonder who actually does the work (looks a lot like Fawlty Towers - everyone is a manager of something!). I've seen some of my co-workers calling in sick because they get pushed too hard and they see no other way out but to call in sick with mental issues. False promises is also a common thing. Instead of a pension scheme they will provide you stock options that "will be worth serious cash!" in the future. Don't be surprised that something that was promised to you gets reversed the very next day.