zoko4ever :
Some site say that phanteks is better than noctua and some that noctua is better.
Really? Here's another of the U14S - no TC12DX, but it has the single fan U14S within 1 degree of the bigger Phanteks TC14PE dual tower cooler with a 150W thermal load:
http://www.frostytech.com/articleview.cfm?articleid=2734&page=5
Anwyay, it probably doesn't matter in the end of the day, they're so close to each other that it's extremely unlikely to make any difference to your final OC. Get what you like. I should concede that I really like Noctua as a company. They offer fantastic warranties, bundle their products with some of best fans on the market, and have a very good history of shipping out new mounting brackets completely free of charge to customers who upgrade their PCs and find themselves without compatible mounts.
They are expensive though, and give 0 choice of colour scheme for those who aren't enamoured with brown on beige. I'm sure there are lots of happy Phanteks customers out there too.