First off, I'd like to say wow! This cooler isn't just another larger than life cooler, it gets in there and handles its business. I even got to play around with this cooler on my current i5 rig, and I am even more pleased than what the testing in the T.E.C.C. testing shows. I like to push my hardware until it screams for mercy, and up to now I have been somewhat limited by air only cooling. While the V10 did alright, for a TEC powered cooler it really isn't worth a degree for the price they ask for it. The Hammer was ok with dual fans too, but there was a saturation point where I couldn't clock any further. With the NH-D14, I have done some silly things already. The major accomplishment I saw so far was that I was able to load my processor in Prime95 testing at 1.5 volts to the CPU, and to my surprise I never saw RealTemp hit 60 degrees. Now that is efficiency!
As far as I'm concerned, there are only two real issues with the NH-D14, and that is size, which leads to the second issue, RAM heat spreaders. Taller RAM like Dominators, Pi series, and loads of others will not clear under the cooler and 120mm fan. I do, however, run Ripjaws, which have medium height spreaders, and I am able to remove and replace them without uninstalling the cooler or fan. In a smaller chassis installation may be a chore, but in my full tower it was really simple. In fact, I installed it with the motherboard upright in the case. A steady hand and patience got the cooler installed in no time at all.
So what are we left with? A cooler that can keep up with both custom water cooling as well as some "modified" air coolers. The main difference is the price. If you look at it against water cooling, it's a no brainer. And for a degree, I'd rather spend $80 to get this Noctua versus a TEC powered cooler for $125. While availability is a bit low currently, there isn't much leeway on the pricing, but I honestly feel it is worth every penny Noctua asks for the NH-D12.