the only century problems I am aware of are the fn fal's they made up and the newer C-93 in 223 I understand many of those are a problem and damm I want one but i wont buy one cause of the reputation.
if the lower is olympic made and the parts are usgi you got a decent rifle,swap out the handguards, my hog rifle ( ar-15) has triangular handguards and a a-1 upper with 70 gr Barnes TSX hogs don't stand a chance