We can compare 14 features from the published specs. The Polk Audio MagniFi Max AX is ahead on 5, the Denon Home Sound Bar 550 on 1, and 8 are ties. The biggest difference for movies is height: the Polk Audio MagniFi Max AX has 2 ceiling-firing channels and the Denon Home Sound Bar 550 has none. Only the Polk Audio MagniFi Max AX comes with a subwoofer, which matters when comparing the prices.