I own and operate Microphone-Parts.com. To the early posters on this thread who traded emails with Kevin, I can tell you that he was the founder but is no longer with the company. Neither he nor I is based in China, but rather in California. I wish he had seen this thread back when it began; I was only made aware of it recently.
To those veterans here who feel that commercial posts are inappropriate outside the white market, please consider two points: we DO sponsor a WM thread, but also, given that the OP was actually asking about my products, I hope this response can be retained here.
It makes be a bit queasy that a legitimate inquiry about my products has devolved into a group buy, which is essentially an effort to buy directly from my suppliers. The Microphone-Parts.com business was started in order to provide high-quality capsules that were not previously available to modders and the DIY crowd. So sad to see this effort "rewarded" by folks trying to save a few bucks. Not that I don't appreciate a discount, but still.
As to the question of the source of our capsules: we use a variety of suppliers, some in the US, some in China, some in Europe. For what it's worth, none of them are WGT.
I'll share some insight into the reality of importing Chinese products, because it is so tantalizing to think that the factory price for something is $28 or whatever. Those of you engaging in group buys should know about the discard rate. Most Chinese capsules are not tested at the factory, and they won't all work. We've seen Chinese capsules with debris under the membrane, with fingerprints on the membrane, with gold adhesion problems, with loose screws. If a "group buy" effort ends up being serviced by one factory I have in mind, 30% of the buyers will be deeply disappointed at the capsules they end up with.
Needless to say, we don't sell those capsules.
You should know about the grading system too. The better factories inspect and grade their products. The best are saved for longtime customers who buy in larger quantities. The rest? Not to put too fine a point on it, but they get sent to first-time buyers who order small quantities.
This ends up working to our advantage, as it lets us bring a higher-quality product to market. We've identified a few trusted suppliers, and we've worked with them to improve the product. For example, some early feedback from the Micbuilders group suggested that the leads could usefully be made longer, so we did that. Also we upgraded to Teflon-insulated oxygen-free copper wire. And we changed the backplate machining on the RK-12. There are more improvements in the works, some of which are significant.
The result is that we have the best capsules for the price on the market, with hundreds of unsolicited customer testimonials (including a couple at the very top of this thread). We offer free US shipping. We provide the mounts, screws and wires. We provide installation support and troubleshooting. We even offer a half-off replacement guarantee if you accidentally put a screwdriver through the membrane during installation.
So, it's a good product, and we stand behind it. If you'd like to see for yourself, I'll throw in a 10% discount for any of you who place an order before Monday, Sept 17 2012. (We don't have a way to do coupon codes, but we'll refund 10% of the purchase price (not including shipping) after the order is shipped, via Paypal. Just make a note on your order or contact us via email afterwards.)
Thanks for reading, and as always, best wishes for your mods.