Which Power Company In Mesquite Has The Best Rates?

Will be relocating to Mesquite, Texas next week and need to pick an electric service but want one with good rates and that has a good reputation. There are many to choose from does anyone have any experiences with TXU, Reliant Energy, Green Mountain, or Texas Power. And what are the major differences between green and non-green as well as positives and negatives? Thank you