I am in an upcoming training class, but I can relate to those who are frustrated with this type of work. Highly trained technical people usually aren't content with a customer service job. That is what this is.
I worked at home for a cable/internet/phone company. The training was fast, brief and skimming. You had to be able to make it work for you. I did. I'm good at researching and figuring things out on my own, so I did well. The difference is the job paid 45% percent less than this and had NO benefits. None. If you go into this job content that it's a customer service position, you'll probably do alright.
As for difficult/stupid people, they are ALL over. I had a lady take a swing at me when I worked in bookkeeping at a bank because she was overdrawn and we'd charged her fees. 0.o I had a lady yelling at me about her Internet not working, and when I finally calmed her down to analyze the problem - her computer was turned off. Yup. Seriously. It's just all part of being a CSR.
For those who are discontent, I hope something turns up for you to truly utilize the skills you have. I am sure it's frustrating for you.