Here's a link to more info on good quality pellets:
Guinea Lynx :: Pellets It gives info on what to look for, and also a list of different brands and what their ingredients are. I've only used Oxbow, and haven't tried any of the others. Oxbow is hard enough to get! I have to drive to the nearest city which is 100 miles away. Luckily, I happen to go there every so often to visit friends/family, but I always have to make sure to stock up when I do go.