I needed 2 of these fans for my Corsair H70 CPU water cooling radiator as the stock Corsair fans didn't have PWM speed control and having the fans spin at full speed all the time was WAY too noisy. :O
Lots of glowing reviews about this fan so I bought 2. Plus it looks cool, it's supposedly dismantleable so you can clean it easily and the bearings are rated at double the life of other fans. That is, if the manufacturers are telling the truth about their respective fans...
Well, they're not particularly quiet nor are they particularly noisy. They spin to about 2300rpm, 300rpm higher than they are rated. They are a little quieter than my stock Corsair fans that also spin to a max of 2300 but I don't think they put out as much airflow as the stock Corsair fans do.
The thing that I'm disappointed about is the inconsistency between fans in regards to PWM control. I initially bought 2 fans expecting them to ramp up identically or nearly identically. NO WAY! One ramped up immediately from 650ish rpm at anything under 30% to 1800rpm by about 60% output power and the other fan barely budged from around 650 to 700rpm until about 70% power output where the other fan was spinning at around 2000rpm. I figured one of these fans was defective and ordered another one intending to send back the defective one. Well, when the new fan arrived, it operated on a pattern about in the middle of the two existing fans. So I have no idea if I have 2 or 3 defective fans or if they simply are all their own creatures operating seemingly on a random power curve. I tested each fan both on my CPU and CPU OPT connections on my motherboard with identical results so I know that my mobo is NOT the issue.
So, in conclusion, it's a good-looking fan that has PWM that may or may not work well with your system. You don't really notice the sound of the fans until around 1100rpm and you'll probably not hear them spin much louder than that unless you do a lot of processor-intensive stuff like video editing or gaming. They're not "loud" (I know this is a subjective term so I am speaking for myself here...) until around 1400rpm, which on my system would equate with about 50C degrees. I virtually never hit that high a temperature. At full spin of 2300rpm, they are quite noisy, though likely not as loud as other 120mm fans. I know they are not as loud as my Corsair 120mm 2300rpm fans.
I grudgingly recommend them because of power curve inconsistencies. I would recommend that you buy 3 or 4 of them to ensure that you get 1 that has the power curve you desire or that you can find a matched pair if you need 2 fans. Then return the 2 or 3 other fans. Yes, you will have to have software to monitor and control your fans and you will have to go through all that testing of each fan at different power output percentages and write down each fan's characteristics. Then you'll have to compare the notes for each fan to find your "keeper" or pair. If that sounds like a lot of work, well, IT IS! I spent HOURS figuring all this crap out! For days I thought I was doing something wrong. That I just couldn't get them to match up. Finally it occurred to me that it could be hardware. Indeed it is. So, learn from my experience. Buy several and return the unneeded ones.
Now, I find it a bit hard to believe that Cooler Master's flagship fan is alone in power curve inconsistency. Could be wrong, but I tend to believe that this is more a PWM issue than an Excalibur issue. So, I'm not so sure if I should be so hard on Excalibur or if I should be hard on PWM fans in general. I don't know. All I know is that this happened to me with Excaliburs. Decide for yourselves... :)