A while back, I wrote on this discussion that I needed to get more information on the dac, and a bit more. Even without knowing anything about Topping, I joined the drop. My experience is that the NX4 is a very capable device. It may not be exceptional in any particular category, but overall, it is better than I expected. For $139.99, it is certainly "worth it". On top of sound and functionality, it has been unfailingly reliable.