Some people tolerate Zocor better than Lipitor
as Zocor is water soluable and is excreted via the kidney verses Lipitor which is metabolized via the liver. If muscle aches are a problem with Lipitor then Zocor can be trialled often with good success.
Lipitor has more potency than Zocor. (mg per mg it reduces cholesterol
better) It is very important to reach your cholesterol goals. In fact recent studies have demonstrated if the blood cholesterol is low enough (LDL about 50 or lower) then there can actually be reversal of the artery plaques.
So you have to balance potential side effects of the medication (or more often FEAR of side effects) with the very bad result of having a heart attack
or kidney failure with uncontrolled cholesterol.
By the way Crestor
is THE most potent medication of the class.