Adrian,


Hi. Basically, SupraSonic summarized it quite nicely. The 10-22 is probably the best wide angle lens you can get for the Canon crop cameras. Apart from Bryan's review, I liked what Roger from lensrentals.com said about the lens (I hope it's OK to quote this here!):


"I’m usually not too much of a ‘Canon snob’ and for most items we carry
several alternative lenses in that focal length. This is an exception –
I’ve tried the other ‘ultra wides’ and the Canon is just better."


http://www.lensrentals.com/rent/canon-ef-s-10-22mm-f3.5-4.5/for-canon


Its disadvantages (IMHO) are two: (a) it's expensive (I really didn't want to spend that much money on an EF-S lens) and (b) for the price, the build quality is really not all that great (but I'm generally an L snob). Image quality is great, though, and it's lots of fun using the ultra wide angles.


Regarding the Tok 11-16, here's a nice review:


http://www.photozone.de/canon-eos/379-tokina_1116_28_canon


Its main disadvanteages (apart from the limited focal length range) are CAs. But, apart from that, it looks like a very sharp lens.


The Sigma 10-20 is OK. Not quite as sharp as the Canon 10-22, but it's a very good value for money (and you get the lens hood and a lens bag too for the price!). I got it but unfortunately I got a horrible copy (very soft on the left side). So, I was put off. Many folks have complained about getting horrible copies of that lens (one after the other too). So, I know that Sigma is maybe trying to save money on doing less QA, but I'm sure having to deal with all the returns is not helping them much...


Hope this helps,


Tony