I recently bought 2 of these and they are great. The airflow through my case is now really good. I've got one as an intake fan on the front of the case and one of these as an exhaust at the rear of the case. There are small arrows on the side of the fan to indicate direction of airflow.
My temperatures have, as hoped, dropped quite a bit. My previous fans only ran at 300-400 rpm so getting some 1000rpm fans has really helped.
Installation was very easy - I chose to use the rubber inserts instead of screws and I was surprised how well they hold the fan in place. It doesn't move at all.
The noise level is also very very quiet. I have my case on top of my desk about 40 cm away from my keyboard and I can't hear the fans at all.
Overall, very good fans, I would highly recommend these if you want some quiet fans that produce some good airflow.