Just buy them from Amazon.
Years ago I bought a stereo amp from Fosi direct and one channel was out. They wanted my to ship it back on my dime. WTF?
PayPal got me a full refund after over a month of much consternation..
Now I have a "mono."
Fosi V3 Mono Break-In
Been playing these amps since yesterday and am quite impressed, but not surprised as they replaced a V3 Integrated...curious about break-in as experienced by owners of these..I use a separate 48/5 power supply for each amp...a friend is putting the Sparkos op amps in his soon...