Tonally, the Yamaha P37D is brighter, clearer and louder. The Angel sounds a bit muffled in comparison. They both appear to have been built in a similar way – injection moulded plastic. I’ve found the reeds on the Yamaha to be more stable, but they will both go out of tune with a lot of playing. The keyboards on both are of similar depth, but the Yamaha keyboard is quieter.
To summarise, I prefer the Yamaha in every respect to the Angel!