I take statins and my Doc told me that the evidence on CoQ10 is not definitive and since I don't have identifiable side effects I don't take it, chiefly because of cost - it's not inexpensive.

This from the Mayo Clinic site:

Can coenzyme Q10 reduce the risk of serious side effects from statin medications?
Answer
from Thomas Behrenbeck, M.D., Ph.D.

At this time, coenzyme Q10 is not universally recommended for preventing statin side effects.

Coenzyme Q10 is a substance made naturally by your body. As a supplement, it's usually sold as a capsule and is marketed under brand names such as Co-Q10, Coenzyme Q10, LiQsorb, Liquid Co-Q10 and Q-Gel.

Some researchers think that taking a coenzyme Q10 supplement may reduce the risk of serious muscle damage (rhabdomyolysis). And some small reports suggest that troubling side effects — muscle and joint aches — from statins might be reduced if you take coenzyme Q10 along with a statin. However, no large studies have confirmed this theory, so current guidelines don't recommend routine use of coenzyme Q10 in people taking statins.

Coenzyme Q10 doesn't cause side effects for most people. However, as with other herbal and dietary supplements, it's not regulated by the Food and Drug Administration.

If you have muscle aches or other troubling symptoms after starting statin medications, talk to your doctor as soon as possible. Statins are effective cholesterol-lowering medications for many people, and it's important to do everything possible to continue taking them as directed.