Do Magneplanar 2.7qrs have a slight curve in thier design or is the side panel warped?

This is my first pair of maggies I notice they are slightly concave rather than straight. Is this a design element or is it the fact that they are quite old? any advice would be appreciatedd. Also Ive been reading that some people recommend putting more ridgid hardwood enclosures on them etc-any thoughts?