Will all of the retail brands like Sapphire, XFX, Asus, HIS, and Gigabyte have models available upon release? If they do, does it really matter which one you get? Are some of the brands better than others? Obviously the Double D model with cost more because it's kind of like a DirectCU II correct?
At this point we can only assume that all the major brands are going to be manufacturing the r9 series. The non-disclosure "agreement" ends on the 15th so we will receive more information on the cards then, but yes some brands are "better" more or less the models are better more than anything else, brand doesn't particularly matter to me but to some people it does. As far as how good a particular model is, depends more or less on the cooling each model will have and obviously, the core clock (but of course driver support, benchmarks, and reviews are important as well.) To explain, its widely expected that the gigabyte models of the 280x will feature their "windforce" cooling, etc. As far as the core clock, your guess is as good as mine. However, all models of the 280x that come out right away should all be in the same ball park, but of course there will be slight differences as i mentioned above. Which also brings us to brand preference. To explain, some people are fixed on the idea of one brand, and that that brand is the best, such is the case with EVGA on Nvidia branded cards, on AMD it tends to be more equally set but i tend to think that sapphire is the most preferred brand among them. As far as bugs go, its again, hard to tell. Usually i wait a month or two before i buy brand new cards, whether or not the "bugs" (if any) will be fixed in that time, im not sure. However, waiting a month or two does give me time to research and look at the benefits of each model of the card, and to read reviews and benchmarks to more or less settle on one card that i feel is the best. Also in this time is a window for drivers to be updated and fix any possible compatibility issues the cards may have. As far as whether of not the cards will get better.. well of course with time comes progression, as seen in the Ghz edition cards such as the 7970 GHz or the 770 SC cards. As far as pricing goes, the 280x is rumored to be anywhere from $299 - $300 USD. The 290x is rumored to be around $600, but of course we won't know this for sure until after the non-disclosure agreement, or until the cards actually come out.
~I hope this was helpful,
Inori.