Hair color?

Hi, Shelley, in one of your recent posts (about the frizzy hair) you said, that coloring makes your hair lot better looking.
I've tried several, including the two sold in health stores, and they all make my hair look OK first couple of days, then (after using the "natural" especially) it starts looking dull, fried, and just totally lifeless.
What color brand are you using?

Thanks