@PENG yes I do agree, but I thought it significant enough to at least mention as it could impact more depending on the speakers involved.
If I was going to buy one of these inexpensive amps to muck around with, this V3 looks like the one to buy at the moment.
It is a good cautionary note, sort of..., relative to most class AB amps especially if the range is limited to 30 kHz instead of 200 kHz. Quite often though, people get mislead by the scale of the graph, such as in this case. If amir had used +5 dB per division on the Y-scale, the curve would look very flat from 20-20,000 Hz.
If I need an integrated amp now, I would for sure try out the V3. It beats so many amps in the ASR chart. Again people will say THD+N is just one metric, but then again, how often do we see amps that managed >80 dB SINAD that measured poorly on other metrics, hardly any!!
I have only one integrated amp, the US$500 (but I got it for less than that in CAD when Bay Bloor had it on sale) NAD C326BEE, that should measure similar to the C320BEE below, it costs at least 4X, yet since I only use one analog input, the Fosi amp would have been a better choice if it was available back then.
The NAD amp would likely last longer but for CAD 110, even if the Fosi amp lasts only 3 years, I wouldn't complain.
My only made in China amp is the Nobsound G2 Pro that uses the same TI chip. It is doing great powering my Energy subwoofer that had its plate amp failed twice. The much more expensive OEM replacement lasted for less than 3 years anyway and I hardly used it. Sometimes people just worry about the "made in China" thing too much, forgetting what they said about Toyota 50 years ago. Even if that's the worry, most, if not all of those cheap class D amps use the US, or German made chips anyway.