There are a couple of issues I want to address up front, but oddly they aren't about the MK-26, it is with what you plan to use this cooler in that is going to be an issue. Most cases are wide enough to take on a 160mm CPU cooler, but the problem here is that once on the video card, the MK-26 stands taller than that, so be sure your case has a ton of room or you run open air as I do. The next issue that needs addressed is the combined weight of the cooler and fans. You can shave a few grams with a selective fan choice, but again if you are running in a standard case, expect a bit of droop on the right side of the video card as the PCB suspends all that weight.
Size and weight out of the way, we can now focus on the MK-26 and its performance. While I did choose some really great fans to cool the MK-26 with, the level of performance is what you would expect from a cooler this big. Once we loaded the video card, in both situations, the results were at least 20 degrees better than the stock solution. What really sells me on the whole idea of the MK-26 is that it was super simple to install. The cooler stands tall enough to allow me to use the stock cooling solution which is also a PCB support rail. So I got the best of everything, including a way to limit the droop that this cooler is bound to cause other video cards.
As I mentioned earlier in the review, the only thing that may hurt the success of the MK-26 is the actual price you will be able to get it at once it hits the US shores. Doing the basic conversion, and if you want to use the fans I chose, this setup is going to be near $110 nearest I can figure. That fact alone is going to keep the MK-26 out of the average Joe's hands and be a selection for the wealthier elitists out there. I will say this for the MK-26 from Prolimatech though; you do get exactly what you pay for with a cooler like this. It offers a very serious foundation for superior air cooling, and regardless of the fan speed recommendations on their site, I was able to easily handle the heat load of the HD 7950 with 2000 RPM fans with enough static pressure to be sure to get all the way through to the heat sinks and the PCB.
If I was in the market to air cool a single GPU video card, the MK-26 is the choice of all choices to make, but if we are looking at cooling a multi-GPU setup, this four slot cooler isn't what you are looking for.