When I got my very first kit, it was obvious to those who have worked in mechanical repairs, to identify that metal is not just metal.
There is not enough space and time to explain my version of how I know this and the same may apply to anyone else who has done or doing this type of work.
The same in principle, I would not know how to identify a quailty hair dryer if I saw one,but a hairdresser would.
So, having said this, take it for granted when we try to express a quality issue and why this occurs, it's basicly the fault of the consumer, that's what it comes down to.
Let's say a HT is manufactured by 6 differant factories in China, and factory A insists on a very high standard of quality.
Everything is finished to a fine art and it takes a day longer to do this. Plus the cost of quality parts adds another $200 to the price of the kit.
Factory F (6th) does the cheapest price, it uses screws that "melt" like plasticine when you try to tighten or undo. The engine runs, but you have constant "silly" problems, such as roller bearings with no case hardening on the clutch pin.
To upgrade this motor your self, it will cost you at the end the same as if you were to purchase from factory A, but it will take you months of trial and error.
Factories B,C,D, and E have various levels of price and quality, so A and F are at either side of the scale.
So, we have Kit A @ $500 and Kit F at $300
We know Kit A is Quality +++
and Kit F is Quality ---
All 6 kits are from the exact same "blueprint" of the HT.
You as the consumer on a budget and time restarints, meaning you cannot afford to be off the road, which kit will you settle for ?
The $300 or the $500, when you already know to get a $300 kit up to specs. it will end up costing $500 anyway,
only thing is you have to DIY.