I think it depends if the student is old grad or fresh grad
Fresh grads find step 2 CK more difficult
Old grads find step 1 more difficult
Step 3, because it's not life deciding and critical, residents find it easy as they just need to pass
Fresh grads find step 2 CK more difficult
Old grads find step 1 more difficult
Step 3, because it's not life deciding and critical, residents find it easy as they just need to pass