Warning: China-Hifi-Audio.com

With Amazon Prime, it seems the safest bet, is to go with near zero risk. 30 days to try the product and not more than 40.00 to ship it back. That is the experience I'm having with the 100LBS Muzishare R100 300B 805 currently running up my electric bill. Coming off a Theta Dreadnaught, my jaw is on the floor at the sound that is coming out of this thing. Your milage may very as its not getting a fully flat single and is being high passed at about 100Hz into powered subs on Vandersteen Quatros, but still. IMO, it is very much worth the slight risks you take with your money, but Amazon has a pretty iron grip on their vendors, nearest I can guess. Ive have the same experience with Chinese DACs as well. Absolutely insane hw good they sound at any price.

RE: Junk from China. This just isn't the case any longer. Understand and embrace the retail price point vs comparable gear from US manufacturers and its a quick study to determine that the value is there, hands down. Be smart about your purchase with a bail out plan in advance so you can unwind with minimal pain (this is called Amazon lol) in the event things so south (or east in these cases).
Far as product performance, I gave the R100 805 a very in depth sonic review in my current system (which uses a Theta Dreadnaught I SS Amp) and after many many hours and three or four configuration changes, I can't make it sound better than my SS amp. This is of no fault to China, or the design, or the parts quality, or topology, or the glued on face plate (which would likely lasted quite a while if it was handled appropriately during shipping)....
Its because (IMO) its a tube amp, with all its non-linearities, just like every tube amp I've tried to replace SS with over the last 30+ years.
I intend to post a full review in the coming weeks.
For what it is, its OUTSTANDING for the money when compared to the multiples (Like 15K-30K) one could spend for esoteric gear that has near zero (if any) sonic difference.