The last time I was at Focus on Imaging in Birmingham, I visited the Sigma stall. They had a new 70-200 2.8 there for playing with. It was very nice but the one on the stand had some pretty awful front focus (not a little) and the big 300-800 f5.6 was a lot of fun....but it was soft wide open over 500mm. Pretty sharp under that focal length....but what's the point in having an 800mm f5.6 if you can't use it wide open? My 400mm f2.8 L IS is sharper with a 2x TC and costs less. I had a go on their 500mmm f4.5, which was nice but again didn't compare to the Canon version. At that point I figured I was done there.
I still own and use a Siggi 12-24mm mkI, which is still a pretty unique lens in the market place. Quality control was awful with this particular lens, but a good one is a good find. I think it's amusing that Sigma have bought out this dock thang....getting us to pay for a device to correct their awful QC and on our time too....come on Sigma. I suspect that Sigma's QC is going to drop even further now...and they will blame their userbase for not stumping up the cash for the USB dock.
for new 70-200 do you mean the lens that won as the best expert lens at tipa awards 2011 or something newer? had the same lens and i had to adjust focus with a +3....so? i had to adjust a canon 70-200 f/4 with a +7...the canon was ff "badly"...lol!
and could you tell me why canon services provides by payment the adjustement of focus for lenses? i do not believe they fix sigma lenses.
and now the brutal fact...sigma 35 mm destroys canon offering costing significantly less...40% or so