I absolutely love Nikon's metering, including the D800. IMO, it's almost always right, especially matrix for informal stuff, and spot.
HOWEVER, my past still haunts me. I sometimes pine for a Weston Master IV meter in my hand as I'm setting up a portrait. Maybe it's a control thing. And I have a Sekonic L558, but it's just too big and bulky.
Now there is the svelte Sekonic 478D, much smaller, lighter, with touch screen.
How many people here use a separate meter for portraits, in place of D800 metering? And I don't necessarily mean you folks with 4,000 kilowatts of strobes in a studio. In fact, I'm more interested in ambient light portraits.