Having heard the entire line of FAD 'Heaven' products against the Grado GR10 before, I can say that none of FAD's products have that hybrid, 'moving armature' sound. The sound is a traditional BA sound.
FAD perhaps doesn't manufacture their own drivers, but I'm pretty sure they do have a subcontracted company that provides them drivers made completely to their specifications and does provide drivers to any other company. I remember someone, probably ClieOS, mentioning that the factory was somewhere in Indonesia, but I can't confirm that statement.
I think that people need to realize that FAD products are almost never a bargain --- not the Piano Forte II, not the Adagio II nor III. The last two are very fun, enjoyable earphones, but technical monsters they are not. What FAD does well is basically all their products give a very distinct, pleasant midrange coloration and significantly wider and open-feeling soundstages at their respective price points. On the marketing and pricing front, FAD is strange beyond all else. Their high-end products are prohibitively priced, but each of them are irreplicable niche products that conventional, reasonable earphones just can't match. In fact, I don't think any high-end FAD is supposed to be a person's daily earphone.
Chalk up these quirky aspects of the company to snake-oil or whatever, but FAD has also been working hard at bringing down their prices for more to enjoy. That is why the Heaven IV is exciting. It's a reasonably priced earphone, and it it delivers the same type of sound that FAD is known for, then it could very well be a success. The fact remains that FAD products are unconventional, in sound, usage, and pricing. If people are looking for that predictable sound from the likes of Shure and Westone, then perhaps they shouldn't be looking at FAD earphones and scoffing at their prices or marketing material.
The last thing I'd like to add is that none of FAD's products are meant for the overseas market. In the last couple of years, they have opened it up to limited markets in Asia, but only reluctantly, and only after strong demand from those local distributors.