Once I get this one done I will take a look at the Muzishare X9 next. It is also a SET 300B and better built than the Willsenton. It also has the clarity of solid state with the warmth of tubes. But it is lacking in bass. It may improve with more run in but I suspect a few capacitor value changes will help. Although I am not knowledgeable enough about electronics to really follow what is happening in the circuit.
It certainly is a fun hobby and I appreciate all your expertise.