I can't find readily any information on where they are made, or from what components, but consider this - the lamps themselves are generally $90 each if purchased from a quality source. If the entire unit costs $100, they are either made from inferior knock off parts, or the manufacturer is not in business to make money. Assuming Checker and others who sell these for $100 make a 50% markup, the wholesale cost is pretty low for HID.
There is a reason that name brand lights run $500 each, and a reason that others are 1/5th of that cost. Especially with an HID lamp, it is the internal parts and the reflector/lens combination that require precision and attention to detail, not the housing and mount. If the ballast and lamp are low quality, the light won't last. If the reflector and lens are not correctly designed for HID, the light output will not be all it can be, even if it looks better than you average halogen. If the unit is a garage-built HID conversion of a halogen lamp unit built with the cheapest parts available, I would not waste my time.
However, if you want HID and can't afford $1,200 a pair, get these and try them. At least you won't be out all that much cash.