Yes, absolutely worth the money. I've had my CHI for 5 years and it's still going strong, there's never been any build up. The only cleaning I do to it is a wipe down about once a year.
My hair is a big frizz ball of waves. It used to take me an hour to straighten my hair, but with the CHI I'm down to about 20 to 30 minutes. I love it!