Need advice from hardware wizards...

I have an i7 950K overclocked on air at 4.025GHz (175 x 23) with hyperthreading disabled.  System has an NVIDIA GTX 660Ti GPU, Windows 7 64-bit, and 16GB RAM DDR3 rated at 1600MHz.  I have stress tested the daylights out of this setup (OCCT CPU 2 hours, IBTv2 20 runs at maximum, Prime95 blend 24 hours) and it is rock solid and runs cool, the cores are no higher than 65c during full load.  I run FSX in DX10 because it is smoother and looks better.  My setup runs FSX/P3D mostly locked at 30fps although I get slowdowns to as little as 15fps in scenery heavy areas (OrbX PAKT with Return to Misty Moorings and FTX Global/FTX PNW).  I usually see mid to low 20's fps in larger cities.  LOD is set to 6.5, Word Not Allowed's settings in use, sliders maxed except for medium traffic and Very Dense autogen. 

And, by the way, many many thanks to the AVSIM hardware guide contributors for their wonderful advice regarding hardware and DX10 issues and setup.  What a great resource!

So I have 2 questions...

1) Does FSX run faster on the same setup with hyperthreading disabled (assuming same exact setup and clock speed)?  I have seen some on the overclocking gaming sites claim that Crysis and other newer CPU intensive games run faster and smoother with HT disabled - this is aside from the fact that OC'ing with HT disabled is more stable and cooler than with HT on.  In other words, they are saying the systems are identical in every way with the exception of HT on or off.

2) Would I see any significant increase in FSX/P3D performance by upgrading to a 2700K/3770K/4770K setup?

Thanks in advance,

Scott