Yea I have had and have replaced those ****ty large CM fans. They push squat for air dude, and they're 230mm.
If you had decent intake fans to begin with the air inside your PC after negative pressure settles will cool your rad just as effectively as an exhaust. THen, you have way less extremely hot air being dumped into your case and being sucked into your GPU. I own a HAF 922 (scroll back a few pages) and had to replace all 3 of those 230mm fans from CM because they are just terrible. Front and side got replaced for Bitfenix Pros and the top houses my 240mm rad with Noctuas. It provided much more airflow for my 580s and 6 HDDs. The CM fan in front at full blast couldn't even push enough air to reach the other end of the HDD cage.
Edit: Ok I sounded like a total dick there. I'm not trying to tell you what to do with your machine or anything. I'm just saying, I've had experience with several of these Corsair units since the year they were released in a wide array of cases (personal and customer builds). One of the biggest advantages to them is exhausting the heat directly out of your case when paired with proper airflow. The HAF series is made for high air flow, but they definitely don't really have high air flow out of the box. If you like it that way and it works for you, by all means.