They look like good fans, But at the end of the day you pay for what you get and at 10pounds they are good value seeing as you can take the rotor off for easy maintenance.
The Zalman ZM-F3 is a very good fan but its plain and simple. But half the price. You don't get led's, nice metal surround, or unique colour.
So at the end of the day its your decision. But I have seen many people use them in expensive builds and they seem to perform very well. I think they are one of the nicest looking fans on the market atm.
Aries 2010 Oc3D Winner
E8400@4.5Ghz 1.4v, Asus commando, HD4870 512mb @ 835/1020, 4gb ballistix @1011, 126.96.36.199, Water, avec thermochill and fuzion, Zalman 850w Braided, Yuraku 24" aou A-MVA panel,
Win 7 64bit pro