Yeah, I don't see any reason you couldn't take it. I still suggest talking to your doctor about switching from Vytrorin to either Zocor (same statin as in Vytorin) or a different type. The latest clinical tests doesn't exactly show Zetia in a favorable light. But, that is up to you and your doctor.
Something that might interest you is a statin/niaspan combo pill. I forget if it's out already, but I believe they are planning one soon.
And only side effects from CoQ10 that I am aware of are possibly minor stomach problems or insomnia (if taken near bedtime). But these are rare, and neither have happened to me (been taking it for years).