Zotac mini 6gb or MSI OC 6gb

Solution
You also have to consider your case size and your thermals in general. The Zotac intakes and blows air directly across the board and out the back. This helps to vacate the hot air out of your case. Something like this is great for a smaller sized case with limited space or exhaust fans; coversely, the MSI card blows air down directly across the much larger cooler and down onto the board which helps to keep it cooler, The only drawback is that it is recirculating the air inside the case and not helping to blow it out.

If choosing between these, I'd personally choose the MSI product. I've built a couple of systems and have always found their products to be some of the best available. Their GPU coolers are always rated at or near the top in terms of design and effectiveness. That's not to say the Zotac is poor quality or anything, but I've never had an issue with any MSI product I've owned.
 
You also have to consider your case size and your thermals in general. The Zotac intakes and blows air directly across the board and out the back. This helps to vacate the hot air out of your case. Something like this is great for a smaller sized case with limited space or exhaust fans; coversely, the MSI card blows air down directly across the much larger cooler and down onto the board which helps to keep it cooler, The only drawback is that it is recirculating the air inside the case and not helping to blow it out.

 
Solution