searching new wide angle lens for my nikon D3100

Hallo guys,

Actually i am looking for new wide-angle lens cause i am interested in landscape photography..just need opinion from you guys with experience in photography. which wide-angle lens is better for my nikon D3100? Tamron SP AF10-24mm F/3.5-4.5 Di-II LD Aspherical [IF] or Sigma 10-20 mm F/ 3.5 HSM DC EX ?

Limited to those two, I would choose the Sigma

I like my 16-35mm VR Nikkor honestly do not know anything about those two.

I'd put the Tokina 11-16/2.8 V2 into the mix. Fantastic lens. Great colour and contrast, super sharp and 2.8!! Similar pricing to the Sigma. Just make sure you look for Version 2, so it will auto focus on your D3100