Tempo ramp vs step


In orchestral romantic music I like to play with tempo to give a bit of movement.
But for this I have to make sure no vsti is based on time because else it kills my cpu. like arcade from output or beat sync things from 8dio :stuck_out_tongue:
Anyway. I like to use ramp to make shapes that are visual.
why using step ? would that use less cpu ? how are you doing it ?