Sigma 10-20mm or Nikon 10.5mm?, WA Lens Options

[clivefrancis]

I have had a look and plenty of topics on these lenses individually, but none comparing the two together (or none that i could find).

so far i have a:

nikon 105mm macro
nikon kit lens 18-70mm
sigma 18-50mm f2.8 which i now use

i am now looking at a wide angle, but which one?

the sigma 10-20mm or the nikon 10.5mm

i know they are different fish, but just how do they compare for build quality speed and more importantly picture quality?

apart from the £200 or so saving for the sigma what are the pro's and con's?

thanks

clive