James (Jim) Johnson , Apr 22, 2012; 10:17 p.m.
"Has anyone used Sigma and Tamron 17-50 mm with Image Stabilization. If yes, please share your experience."
My Tamron 17-50 f/2.8 does not have Image Stabilization, . . . So, I suppose my experience may not be of any use, but I'm going to put my short .02 cents in anyway!
It is claimed by many that the non VC (Image Stabilization) version of the Tamron 17-50 f/2.8 is sharper than the VC Version in many of the reviews. However, a friend of mine has the VC version and I think his photographs are just as sharp, and I think we both shoot with about the same techniques.
I've had my Tamron 17-50 f/2.8 for about 4 years, and I personally have been so pleased with it's results that should it fail for any reason, I'd be first in line at the nearest retailer to purchase another.