EVGA SuperNOVA G3 vs P2 (850W)

[Prozn]

I'm trying to decide between these two power supplies... The P2 is more efficient but an older platform by a few years, and one centimetre longer.

Is it worth going for the G3 purely for the newer platform?

I can get either one for an identical price.

 

[Prozn]

I do not need 850W no - it'll be an Overclocked 8700K/Overclocked GTX 1080 (2,100mhz) build with 5 hard drives, AIO, 4 other fans. However, this PSU will be lasting me for a long time, and the marginal increase in cost for the extra potential is worth it in my opinion. At the very least it means the fan will be unlikely to spin up.

That Seasonic looks excellent. However, I plan to use custom cablemod cables, and the Seasonic doesn't appear to be supported. Purely cosmetic I know, but there it is.