Nikon AF-S 35mm f1.8 G DX Lens

I have a D3100 and was looking to purchase the above lense soon for portraites and low light pictures, but after looking on a few sites some people are not giving it good reviews and saying that the 50mm lense is better, but as my camera has a smaller sensor I didnt want the 50mm as it really makes it approx a 75mm and the 35mm will be approx 55mm ( am i correct in that)?.
Also I have read that the lense can only focus manually on the D3100 is this also correct??
Please help

The 35mm f1.8G DX lens will AF on any DSLR camera and it is a much better focal length for normal field of view using a DX camera.

gqtuazon thanks for that, so is it a good lense for Portraites and good at creating a good shallow depth of field

You are welcome. You can appreciate this more if you set your zoom lens to 35mm and then try it at 50mm to get a quick glimpse on the field of view.

The closer you get, the shallower the DOF will be.

gqtuazon thanks I will try that as soon as I get in from work

I just bought mine today, and let me tell you WOW. I am soooooo happy I purchased it. Super crisp photos.

The lens will work fine with your 3100 and yes auto focus will work too, it's an incredible lens for a great price.