I have had a worm farm for 1.5 years, I have not had any problems with mine.
One of their favorite things to eat is cardboard, tear it in small pieces and wet it before burying it in you worm bin. Like beeman said, you do have to be careful not to put in more waste than the worms can take care of. I started with 500 worms (they were small) and it did not take as much to feed them as I thought it would. It has been interesting, they are trouble free, I have mine outside but there is no ordor. We had a colder than normal winter in East Texas, when the temps dropped in the teens we moved the bin in my husbands shop. There's a lot of infor on the net.
Enjoy,
Neva