should i use hot rollers instead of curling iron?

i have this straight, soft hair and whenever i use a curling iron to curl my hair, my hair will starting un-curling after like an hr or something if i dont apply hair spray. does hot rollers stay longer?
then, my friends told me that maybe i should use hot rollers instead of curling iron since my hair is really straight.
is it better to use hot rollers for straight hair?