I originally built a gaming rig with the 200r(http://pcpartpicker.com/b/sfgLrH). While the case was nice, it just didn't have enough space and the front intakes were not only limited to 120mm fans, but the 2nd fan had to push through a hard drive cage. When I looked up new cases to get I was split between the Define S and the Air 540. Since the Define S allows for 8 140mm fans as opposed to the 540's 5 it was a no brainer. I also made the mistake of getting a 4460, thinking it would be enough. I noticed how weak it was about a month ago.
The 4690k was only 199.99 at Microcenter which was the best price I could find both online and in-store. I overclocked it to 4.4GHz with load temps hitting around 65c. Didn't see a big enough reason to buy a new video card when the 280 was working just fine. Since I had the option of using 8 140mm fans I decided to use them all. The top 3 are AF140s set to exhaust, the rear exhaust is the CM Essentials 140, which I chose due to it's low RPM since I had to run it in the PWR_Fan header which sets it at 100%. The front intakes are the 2 GP14s the case comes with and the stock fan the Evo 212 comes with. Newegg decided to split my shipment up and caused my Deepcool to become really delayed. I replaced the Evo's fan with the Jetflo 120, because it has blue LEDs and amazing CFM/Static Pressure for the price in addition to being 4pin. I had a spare SP120 from my previous build lying around and I still had the CPU_2 header left so I went ahead and added it for the bottom intake.
Overall the case is amazing. There's so much room and with the hard drive cage gone it means there's almost no airflow interference and building in it was a breeze. The window is a nice addition too for only $5 more than the non-window'd version. In speedfan I've got the fans to only go above 40% when under load temps. Outside of that the case is quite silent since the highest RPM is only 1100 from the rear exhaust. Everything else is 600 or below.
Plenty of space, rubber grommets in all the right places, hard drives out of the way mean there's nothing obstructing the airflow you need for your GPU/CPU. There's also plenty of space for watercooling and more than enough space for air cooling with room for 8 140mm fans. Plenty of clearance space for large CPU cooling towers too.
The screen scratches extremely easy and I do wish there were more grommets at the top or that the sole grommet at the top was a bite wider.