Safe gearing for 6s on Flux?

Ok, after thinking hard about this, I really wanna try and experience 6S on my 2nd Flux. My first Flux did have plenty of go with 2S 6000mAh 28C SMC but now I wanna see first hand what 6S is like on this bad boy. After much research and forum searching, im aware that dropping the pinion gear down a few teeth will help reduce strain on the Lipos and reduce heat on the ESC and motor.

I plan on getting either one of these for 6S power. Any input?

http://hobbyking.com/hobbyking/store...dProduct=11939
http://hobbyking.com/hobbyking/store...dProduct=12936


Should I change my stock gearing from the 20/44 and go to 18/44 or should I go even lower? I wanna be able to still go faster then 4S at 20/44 but I don't wanna blow my ESC either cause I will be driving in variety of conditions while bashing and jumping.

Thanks all for your input and patience my last few threads, I just want to make an informed decison