On the various forums Sigma lens seem to have a quality control problem and it seems to be hit and miss, I can get a couple of lenses via the tesco deal at half price, but wonder is it worth the gamble 
I take general shots, family etc, like landscape, city scape and am thinking about trying a prime or two as I have the kit lens 17-85 on a 50d and some old canon zoom lenes.
Is the reliability of quality better on either of these
sigma 10 - 22
sigma 30mm F1.4
confused what are your experiences

I take general shots, family etc, like landscape, city scape and am thinking about trying a prime or two as I have the kit lens 17-85 on a 50d and some old canon zoom lenes.
Is the reliability of quality better on either of these
sigma 10 - 22
sigma 30mm F1.4
confused what are your experiences