Over the past 12 years or so I have taken Lipitor, Pravachol and, when 200mg total Cholesterol wasn't good enough anymore, Vytorin, which brought it down to 160. But, at the end of all that about two years ago I wound up in the ER with severe kidney problems. The doctors said, don't worry about it, just muscle pains and sent me home. Since the pain (enough to climb the walls) started at night and I took the Vytorin at night, I concluded, it must be the Statins and I quit taking them and, just as I thought, no more pain. Now I am taking Crestor 5mg's because the cardiologist said, I should be taking them again. Since this was only four weeks ago, I can't really answer your question, but from my experience, they are crap, not only based on what I just described but also during the time I have been taking them my Calcium Score went through the roof. Now, the pat answer to that would be: "If you wouldn't have taking them it would probably be much worse." But why then do they advertise: "Will prevent plaque" and not "It could be much worse if you don't take them."
Studies have found no links to incremental side effects with long term use. Your dosage is quite small, most all side effects occur with doses of 80 mg per day. Just make sure to get your blood tested annually to make sure there are no changes in your liver enzymes.
Hope this helps,
Jon