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.
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