Actually never heard of them. I did a little research out of curiosity and found their website which looks relatively well made. The website says a lot about the people. The links to social channels in the footer of the website are:
Facebook: a link to an unavailable page;
Twitter: sends to the profile of a bloke called Hittey king (with also posts photos of his dog );
Pinterest: a fake link;
Linkedin: a fake link;
Google+: this social was closed quite a time ago.
They have a strange solar charger that looks the same as a Victron (here):
Found some AU guys talking on Whirpool's forum (here) about this particular model: "Fangpusun gear which is an exact Victron clone or out of the same factory (even down to components and firmware being the same) but anyway do a search plenty of people using Fangpusun stuff without problems and for 1/3 of the price".
A part from that the offgrid inverters look awesome but maybe you could search some reviews of those!
Fangpusun copies and then sells the XTM and XTH versions of Studer inverters. Studer supposedly is opening an office in Miami, but for now is still delivering product from Switzerland. They are also showing what looks like a similar product to Studers' new line called "NEXT"
The Fangpusun units are not made in the same factory, but supposedly source many of their parts from Germany and Japan. The pictures on line of their products show very nice workmanship, and numerous people have given them pretty good marks. Of course, you can never know for certain if those photos were actually of their units, or an actual Studer.