w/a curling iron , I have to spritz my hair w/hairspray b4 i curl and then the curls last until the next day. If i don't spritz each layer , then curl and spritz again, my curls fall apart after an hour.
W/the CHI, I think because of the high heat, my curls stay curled after I wake up the next day .. but i only have to spritz my hair lightly after i finish curling my entire head. (which is a lotta hair .. lol)