3 120mm cougar fans @ medium to high speed= I must wear headphones. Heh. JK, kinda. They were noticeably louder at both idle and full speed. But if budget is a factor, then I'd have to agree with you that they're ok. Cougar and BitFenix both make decent budget fans but honestly
I'd rather spend five bucks more for fans that are quieter, move comparable air and most importantly, have high quality bearings that will likely have twice the lifespan, regardless of how many hours they say they have on paper. I've replaced Cougar PWM fans that were supposedly 300,000 hour fans that were just installed two years ago, so although they might be "specified" to last that long when tested in a lab, I tend to go with what I know is a higher quality bearing. Besides, to determine that fact they'd need to run the fan for 34 years, which I know damn well is impossible to have done.
Their "estimations" leave much to be desired when there is 8675.81 hours in a year and multiplied comes to 34 years of testing. Lab testing rarely equates to the dust, hair, grease and other contaminants in real world use that most rigs see in the average users home. Spend five more bucks per fan and get a quality product if you want them to last and keep their performance. Cheap fans tend to work well at first but lose integrity as time goes on.
I've got test fans from Cooler master, Corsair, Cougar, Bit Fenix and Aerocool that were all pretty satisfactory at first, but after many hours of running in test configurations in and out of various machines, are not nearly as quiet, nor as fast, as they were when new.
Conversely, I can't actually say I've ever had to replace a Thermalright, Noctua or Phanteks fan that I've installed. Yet.
Of course, now that I've said that, all five in my machine will probably die tomorrow. Eh, maybe not. The only fan in my case I worry about is the 200mm CM Megaflow, which is hitting the road soon anyhow when I change cases.