Hey JohnSpeed.
To answer your first question bluntly (in my understanding thus far), the answer is "none".
The reasons for this are many. Unfortunately, you'll never find "the same quality" in a generic chiner frame that you will find in a Scott, Giant, or Specialized. The reason is because "quality" comes from a number of areas... some of these areas occurring after the production process. There is always that possibility (not necessarily a myth) of frames going out the back door of a factory that would have otherwise been supplied to a big name-- and this might be closest to "the same quality" that you refer to. Of course, the big brands have an interest in this not occurring,
and even more so, the OEMs may have an interest (to put it mildly) in this not occurring, as their clients are the big western brands. There are many stories of apparent "grey-market" frames out the back door, counterfeits that are nearly identical and never have an issue, or nearly identical and then fail after a year, etc. etc. It's really a difficult one to comment on with authority, or to say specifically where or how you could access a guaranteed product of "the same quality" through this kind of channel.
However, there may be some areas of "quality" you would be happy to sacrifice for a lower cost. This is, I think, the whole point of forums like those on Chinertown and MTBR, right?
If you want to know which OEMs are manufacturing frames for the big brands, you can find that information online. A good primer (thought a little old now) is
here.
If you want to know what other frames leave the same OEM that manufactures a big brand,
some of that information can be found online, and some of that would be accessible to me through networking or visiting a factory here in Guangdong. Some Chinese websites have this information, but you would need to be able to read Mandarin. Some of my Chinese friends, or friends of friends within the industry do know some of this information, and that actually might be valuable information to compile into an e-book, website, or listing of some kind.
In my understanding, the OEMs that have contracts with top-tier global brands (like Scott) as well as those who produce high quality frames solely for the Chinese market (my partner rides for a decent Chinese brand called
Camp, manufactured by the OEM
Shenzhen Kespor Bicycle Co., Ltd. will be
capable of producing quality products. Obviously, right? These OEMs would be valuable to locate, and to query as to which frames they manufacture, and where they end up.
I think I'm sort of back-engineering a question underneath your question... which is everyone's question... where can we get a great frame at a great price?
I should say, publicly, at this point, that there is the ethical dilemma of counterfeits... either out the backdoor/on the black market, or in a design cloned by a different OEM than the one supplying frames for a big brand. I've seen websites/pages taken down by the big brands because of this; today I saw one that was there a year ago shut down sometime recently by Specialized.
There are different tiers of quality-- in terms of design, materials (for instance: carbon), processes, quality assurance, and support. There's another category in there I'm missing at the moment but it's getting late here
Alot of that information is available here on Chinertown, on MTBR, and elsewhere online, although having that in one place (an e-book, website, or listing) would be useful, too, for reference.
Thanks for sharing your interests/questions. That gives me some ideas on what information might be useful to compile. Hopefully that primer I linked (and its links) is useful and/or interesting to you for now. I can't fully comment now on things like the backdoor/black market frames as it's nothing I've experienced firsthand... although it might be interesting to investigate. Most of the "counterfeits" or clones I have seen were laughable, and Specialized wouldn't waste their time chasing them down, although it is annoying to see your name being used to sell products, I'm sure.
That's a completely different topic related to manufacturing and marketing here in China...