A few things to keep in mind with GPU's...
Warranties are often pointless if the device works as advertised for about a year. Most computer equipment are either fine out-of-the-box or DOA, very few ever fail more than a few months after purchase.
Warranties are often moot after a year or so due to the GPU upgrade cycle. By the time the warranty ends, most manufacturers are already producing or selling next generation GPU's.
Overclocked GPU's cost more for something you can do yourself at home in software, so you can save money that way.
Most GPU's are reference designs put out by AMD or Nvidia. This means that the cards themselves are identical between manufacturers with the exception of the cooling device. There are exceptions to this, but those are really niche cards that are expensive. In other words, an HIS 6950 is technically the same as an Asus 6950, Sapphire 6950, Diamond 6950, etc. This also means that a review for any card will be a good indicator for all other cards in the series regardless of manufacturer.
Typically, the only differing factors between the cards are the warranties, bundle, cooling device, and, sometimes, ports on the back.
The HIS IceQ X H695QN1G2M Radeon HD 6950 1GB
I linked to in an earlier post does come with a two year warranty and Newegg will take the card back for an exchange if it is DOA. All GPU manufacturers offer a warranty and Newegg always lists warranty information on the product page under the "Details" tab in the quick info section on the right hand side.