Is CertainTeed really better than Mastic, Norandex and other vinyl siding brands? After more than 20 years installing siding, I break down what actually sets CertainTeed apart, including Monogram XL's 25-foot panels, CERTAplank, siding thickness, colors, profiles and installation features. Find out where CertainTeed genuinely excels, where competing brands measure up, and why it's our preferred siding manufacturer.