Dont get caught up on CPR rate on this, since pressing two key on keyboard is NOT realistic!
Sing Nelly Elephant or Archers Theme tune or Staying Alive...
I use these Manikins on my courses, have LED lights on Shoulders
As i said good refesheher, but nothing beats Hands on practice on a Dummy (apart from real person but hopefully we will never need to do that)
STRESS DON'T PRACTICE CPR ON REAL PERSON