Nikkor 50mm 1.8G or 40mm 2.8G?

I own a Nikon D3100, i wanted to buy a lens that would be good for portraits, i have already owned 50mm but it didn't autofocus on my camera, so now i want to buy the G lenses so they will autofocus, but i'm stuck between the 50mm and the 40mm, the 50mm is out of stock everywhere except Ebay and it would be coming from Hong Kong, i'm kind of scared to buy from there, and the 40mm isn't out of stock, but i don't know if it would be good for portraits and i kind of like that its macro, even though i would mainly be using it for portraits, and i'm not interested in buying a 35mm since i already own a Sigma 28mm.

Personally, I would wait for the F1.8.

I'd go for a 50mm f1.8G as you'll have more depth of field control, less distortion, and you won't have to get uncomfortably close to your subjects.

if you already have the 50mmD, you could consider upgrading the camera body instead.

Up to you. You got a zoom that can do 40 and 50mm. Use that to determine which focal length works for you. I'm expecting the 50mm to be in stock again in two weeks.

Hey i'd pick the 50mm.
here's a search on ebay you could look at & try to win the 50mm 1.8G in an auction i've seen a few buy it now prices too. Good Luck!

http://www.ebay.com/...86.c0.m283

Why is it you do not want to manually focus your portraits? There's an electronic rangefinder in your viewfinder you can use to make certain that you are focusing the subject. Photographers have been manually focusing their subjects for decades. Just take your time, focus and compose your portrait and squeeze the shutter release.

NOTE: the 50 mm is probably the shortest lens you will want to use for portraits. The other option (but far more expensive) would the the Nikkor AF-S 60 mm f/2.8.