I have this case and for the moment i didnt put fans on the top, but the other fans I have them positioned as you are showing. System is 1 year old and i never get above 60 degrees cpu (i7 930 2.8ghz with N520 coolermaster) and gpu never over 65deg. (hd5870).
I have been thinking to put fans on top and i think the most effective would be to have:
//// rear //// middl //// front ////
//// push out //// push out //// push in////
//// cpu //// ram ///
thats what i said when i bought that case too but 1 year later my head get dizzy from the CPU cooler's fans because this case is a kind of open-air case which mean you hear 100% of whats going on inside.
But anyway, if you have no prob with noise go put those fans you'll have a nice cool case with perfect airflow
The fan profile looks pretty good. I would say the same thing as tlg, consider fan 3 pushing in. I would also consider moving one of the higher speed fans to be an pushing fan. That way you should have a more positive pressured case and therefore keep a bit more dust out.
Also don't forget that these will not be the only fans in your case. You will have many other components that all have fans as well. So when thinking about the air flow in your case I usually find it better to keep the basics in mind (fans in front/bottom push in, fans in back/top pull out) but use those to aid the fans already inside.
Aka make sure your top fans are aiding your CPU cooler and make sure that you are thinking about where the hot air from your GPU will be going and the quickest way for it to get out of the case.