Better Fans?

I was just wondering but, are the fans from the NZXT Kraken X60 good fans or bad fans?

If so, what kind of fans should I get ?

So far I know that fans are required to be about 140 x 140 x 25mm each one, so I wanted to ask that, If the Fans from the Kraken are bad, can I have suggestions on what kind of other fans I should get, and if there are better Fans out there that I can use, can you also give me suggestions.

one word: noctua.

+1 for Noctua NF F12 120mm fans or Noctua NF P14 140mm fans (I forget if the x60 is a 140mm RAD or a 280mm RAD) They aer ugly as fudge, but are the best fans on the market. If looks are more important, then I recommend Corsair SP120mm fans or Scythe Gentle Typhoon 120mm fans. But Noctuas are better ;)

+1 for Corsair SP120, suck my dick Trebek.