At what age should a person first be checked for plaque in the arteries? dont tell me "only if you have symptoms" i don't take any chances. what age?

It's not so simple: The problem is that there is no proved, effective test to check for plaque in the absence of symptoms. Controversial methods include "calcium scanning", ultrasound, and others, but most experts consider them unreliable. Even if abnormal, without symptoms usually there is no treatment except what should be done anyway (no smoking, exercise, weight and BP control, drug Rx if abnormal lipids, etc).