I have built a couple of these in readiness for my stereo subwoofer project, although I haven't powered them up yet. I intend to double up the power MOSFETS for the sake of headroom.
This isn't the most sophisticated of circuits, eschewing the use of frivolities such as current sources. The THD is specified as "better than 0.1%", and the slew rate is less than 10V/us, but it's a pretty indestructible circuit, having been originally intended as a guitar amp! I reckoned that the relatively low distortion at low frequencies and its robustness made it well suited for subwoofer use.