Something you may want to try. If you do, report back with results.
For cooling you may be able to eliminate all but one of those case fans if you do what I have done.
Just for testing purposes, for now, I bought a piece of plexiglass and cut it the same size of the side panel. I cut a hole to match an 80mm fan exactly oppsite the cpu so that room air is blowing directly into the cpu cooler fan. I also rigged a square tunnel made of poster board from this fan to the cpu. My temps run at 39c while room temps are at 25c and system is 34c. This is a long shot from before when I had two case fans running. The cpu temp with two standard case fans ran most of the time at 50-52c.
I used the plexiglass because the hand hold of the case panel was in the way of mounting the fan onto it.
If you are having a cooling problem you should try this to see if it will help. It cost very little.
The fan I am using that is mounted on the plexiglass is a Thermalltake variable speed but I am only running it at 3000rpm. It will go to 4800rpms. It is the A1357 Smart Fan. The cpu cooler is a Cooler Master HCC-002 all copper base.

aka the tube of death. dont know why. to make it look better mount the fan in a subwoofer port.ie; case side/sub port/case fan/hsf.

Rooster, what does all that mean?
Side note: I will try what Buster65 says and will post results. It sounds logical.

little hard to explain without pictures.basically start with a subwoofer port(you know- the plastic funnel type thingie that lets the sound out of sub woofer enclosures, like a home stereo sub), mount a case fan- prefferably 80-120mm- to the inner( smaller) end, cut a hole in the side of your case inline with cpu cooler and flush mount port/fan assembly into said hole. looks trick and has venturi effect due to the ports taper.

I guess my butter tub doesn't look quite so trick. I'll buy a brand with a nicer logo and try again.