I have bought some parts from them, via their eBay shop in the UK. As far as I can tell these are exactly the same parts as used on any name bass etc that is manufactured in China or the Far East.
A lots of manufacturers who outsource their building and parts appear to use this supplier. For example, I ordered a 8 string bass bridge which appears to be identical to that on a Swedish branded made in China 8 string bass.
Similarly, I bought a 4 string bass bridge which appears to be identical to the bridge on the less expensive version of the Billy Sheehan Signature series model.
The tuners/machine heads that they provide unbranded appear to be identical to tuners/machine heads that carry the name of various brands.
Some Internet research should indicate those manufacturers who have set up factories/production lines in China and other far Eastern countries.
I did read somewhere that during the 1990s and the revival of the traditional two hum-bucking, single cut type guitars made famous by Slash that a lot of these guitars although they had a famous name headstock actually had parts outsourced from the Samick company in Korea.
At one time Samick were the biggest makers of guitars in the world both under their own brand name and also as the manufacturer of "named guitars" for various famous companies from Japan and the USA.
A lot of these parts will be found on any guitars that are manufactured in China or the Far East.
Personally, and I have no affiliations of any of the companies mentioned here or alluded to, I have found that these parts do their job.
Thunderbird Club Member #265