Honestly I think that the decision should be made based on what you use the machine for. For example, if I were in your place (price not being an issue...that's an amazing place indeed) I would probably choose the 5960, but that's because I use my PC for other tasks like music production, occasional video transcoding, and other things in which the cores/cache make a MUCH bigger difference than the clock (though I'd probably get a water cooler and overclock it to death). In this case, from my limited knowledge the bulk of FSX performance is based on clock speed and single-core performance, so if all you use the machine for is FS than by all means, get the 4790.

 

Getting a high-end graphics card with an ample amount of VRAM I think will help texture/add-on performance more than additional CPU cores/bigger cache.

I7 4790K is the best i Built it in my new system with a GTX 780 3 gig and also used a Z97 Gaming 5 motherboard MSI, I love the new RIG and getting awesome performance like the other guys with FTX Global and Vector and FTX Australia Regions and airports i dont see below 26FPS flying into add on airports, FSX standard airports i see about 35-40fps and this is with sliders to the right and flying the PMDG 737-800

 

I water cooled and overclocked the I7 4790K to 4.5ghz and was steady at didn't go over 60 degrees i could of went more but was happy with the results with FSX 

I just wanted to thank everyone for their input. I ended up going with the 4790K and 16G of RAM and a GTX 980 video card. I haven't assembled the system yet but it's definitely going to be better than my old 2009 system no matter which way I went

 

Thanks again