Building a new upper.

So im looking at building a new upper for my ar and have been looking into either the 6.5grendel or the 6.8spc. I was wondering what your guys input on either one of the rounds are?

 

if u want to go with 6.8 SPC go to 68forums.com thats where i got a lot of my information when i buit my upper

 

it's go 6.8 SPC, It seems to me like it's becoming the more popular "non-nato AR round"

I'd be building a 6.8 if it weren't so damn expensive.

 

the main thing u want to look for when getting a 6.8 SPC is get a barrel thats Spec II with a 1:11 twist or slower or a barrel marked 6.8x43. either one of these have updated specs and will allow u to be able to shoot hotter loads with less pressure in the chamber