Originally Posted by deejjjaaaa 
Sigma too is assembled in Japan and has enough qc issues - however my dealings w/ their service center last year (about 17-70/2.8-4.5) showed at least one positive things - they will replace the lens itself fast and no questions asked for as many times as you want it...
because they know how many QC issues they have? I see that as a bad thing actually..... not positive at all.... more like necessary. glad I don't buy sigma.