sigma10-20 v Tokina 12-24

Dear guys

I am torn between these two lens but leaning towards the tokina. I don have the cash for the Canon one.

tell me how important do you find the extra 2mm at the wide end?? I will be using it for all sorts of shooting, from documentary to architecture and landscapes.

the tokina has a better build (i guess) and constant F4. does the tokina has quality control issue like that we hear about sigma??

please, let your experience come out and help me.

A big thanks in advance

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Mobasser Hussain