Lens choosing (Canon or Sigma)

Hi.
I have seen a fair few pages around the internet about the comparison of Canon 10-22mm and Sigma 10-20mm

I definitely believe the Canon to be the better lens but what I want to ask is what do you reckon is the better lens when you consider the current price? Here's what I've found:

Currently from Amazon the Canon 10-22mm lens is £422 and the Sigma 10-20mm is £294 although the Sigma includes a hood, Canon charge £24 for theirs.
I do like Canon lenses and always try to buy them but their is a fair jump in price. Also I keep seeing about 1 in 3 of the Sigma lens having issues with part of the picture being blurry.
I'm a keen landscape photographer so this will get use in that field.

Taking all this into consideration what would you recommend?
Thanks in advice

Have you compared images from these two lenses? Here at Photography Review you might want to search the Gallery and look in the Reviews Section to see what real photographers of a wide range of skill and frequency of use can truly achieve.

The higher end lenses I've used from Sigma have a similar failure/bad rate to Canon units. The less expensive/kit lenses from Sigma have at times been maligned partially from inexperienced users or from those expecting to get something for nothing. Also they are not as sharp at maximum aperture as they are not designed that way as are many of the Canon 'L' units. Then again there's an order of magnitude difference in price in some of the lens units as well!

There is the consideration the Canon EF-S will not fit on some older cameras that the Sigma apparently will.

Sigma is quite responsive to warrantly issues , at least in the US, and will repair or upgrade chips as needed to make their gear work.

It's always a good idea to check the reviews on this site. My two cents is that the Sigma is every bit as good (maybe better) than the Canon. I have used both and own the Sigma. I am, like you, one who normally stays with the Canon brand lenses because they have been so good to me in the past. I don't think I would buy a Sigma tele lens. That said, the Sigma proved to be a few things to me when I compared them side by side. First, it's cheaper. Second, it's sharper (albeit barely.) In pixel-peeping images taken with both lenses, I believed the Sigma to be better. Third, the image is more rectilinear. In fact, it's more rectilinear by far than my Canon 28-135. Comparing architectural images taken with both lenses, the Sigma did better at the same focal lengths. Fourth, the build quality is just as good as the Canon (again, maybe better.) It being an EX series lens, the finish is very good, it comes with a lens hood, and the HSM focus is just as fast. Fifth, it works on any EF mount. It is usable on my Elan 7. Of course, there is significant fall-off and vignetting at 10mm, but I can use it at about 13-14mm without any trouble at all. Depending on your stock of Canon bodies, this may or may not be a selling point for you.

Hope this helps. I (stupidly) didn't save any of the comparison images, but could post some 100% crops of images taken with the Sigma if you would like.