Originally Posted by Shapeshifter
I also want to populate the 140mm fan mount right beside the psu and having a smaller body length psu would be a plus, make things easier cable wise in that area.
Can confirm. I've got an EVGA 1000 P2 in my Define R6, along with a 140mm intake on the bottom and she's a tight fit... cables protrude out from the front of the PSU and over the edge of the fan.
An 850 G2 is a little shorter than the biggest P2 models, but it's still longer than your average PSU. The 850 P2 is standard size, though. Planning to downsize mine as well, if I can snag one of those for a decent price.