Pros: super quiet
economical
I here my mini fridge across the room and not my computer fans running. how sweet it is!! lets see how long it all lasts.

Cons: haven't seen any yet, just installed in my tower a week ago.

Other Thoughts: so we built this computer for music recording purposes and one of the biggest areas of focus for our build was for it to be quiet. so i have some monitors running in the background for the sound system and their little hiss makes more noise over my pc, It is so stinking quiet. I am very very pleased.

Pros: great fans. move a good amount of air and are not loud

Cons: none

Other Thoughts: yes I would recommend these

Pros: Bought this as an additional intake fan for my Fractal Define R4 blackout case because I wanted it to match. Does the job exactly. Fan is very quiet even at 12V and I'm happy with the cooling difference it's made. I didn't need to use any of the included hardware because it snaps right into the front mount of the case, so I have no idea if there is any sound differences when using those.

Cons: It's a bit pricey for a basic fan. It was worth it for me to have it match the other fans in the case. May be less of a worthwhile buy for people who don't care about aesthetics or about wanting a quiet fan.

Pros: Good

Cons: Actually pretty loud compare to the ones my s340 case came with, it might have to be because I connected them to my power supply rather than motherboard tough.

Pros: Quiet, easy to install

Cons: Slightly expensive, purchased as an extra case fan for my Fractal Design RF4, just got the same fan

Pros: Perfect match for the R4 Blackout Case and the black-on-black fans it includes.
The 140mm fan snaps into the optional fan spot in front fan cage without any of the included mounting hardware. Other optional mount positions use mount hardware though.
Comes with screws & anti-vibe rubber gaskets, alternate stretchy-rubber mounts and an in-line power reducer if you need one.
Very attractive black sleeved cables.
Super quiet and free of any vibration noise.

Cons: They cost a little more than some other fans and they weren't on sale when I needed them. But I think they're worth every penny, so not a con.

Other Thoughts: I got this 140mm and a 120mm to flesh out my new R4 blackout model case. Nicest case I've ever worked with and these fans were the perfect compliment to the setup. Fractal Design makes some really nice stuff, doesn't cut any corners and stands behind their products. The small details, the engineering makes their stuff so nice, like the little touches you find in a European car, as compared to an American car. "Wow, they thought of that..."

Pros: Very quiet, pushes enough air to make me happy

Cons: Nothing

Other Thoughts: I had the white set of these in my Fractal Design case and loved them so I got them for my new build! I'm using the Phanteks Enthoo Pro case and I don't think I can really hear them especially for not being in a silence optimized case. I think these run under 1000rpms constantly, more around 650rpm at idle because I can lower the rpms with my mobo

Pros: Needed additional case fans for my R4 blackout case. Decided to order these to match the OEM fans.

They are incredibly quiet even on 12V and I feel a lot of air flowing even with dust filters on.

Cons: None.

Other Thoughts: There may be better performing fans but my case is all about silence and cooling and these seem to fit that niche well.

Pros: Matches the Define R4 Blackout case I got.
It is fan. Seems to be on the quite side of fans I have dealt with and is made well.

Cons: Pretty high for a fan...

Other Thoughts: Price went down after I got it.

Pros: I have 4 of the standard white versions and now 2 of these black ones. No different, all are very quiet. Good price on sale. No led's

Cons: air flow is uneven. It tends to shoot out around the edges of the fan. This doesnt seem to have any effect on cooling in my case. I have 2 on the front and one in back pushing in, with one on top pushing out for venting. This is in a Fractal r4 case. The whole setup runs very cool and quiet.

Other Thoughts: Another commenter stated that these fans produced some noise when mounted facing either up or down in an exhaust fashion. Due to that review, i tried both of the black fans i ordered immediately in both configurations and didnt get any additional noise. One of the fans has now been in a vertical venting configuration for a couple of months without issue.