I'd definitely take the NH flight, though not because the NH product is really significantly better on this route. 80 minutes is tight for a connection at PEK if anything goes wrong (even transit passengers must clear immigration), and HND is almost always preferable to NRT. You'll save most of the time on shorter immigration lines at HND (although this is less of an issue if you're a resident) and the much faster train ride into town, and you won't have to rush and worry about missing your plane at PEK.