I have read that Sigma is bringing OS to the 120-300 f2.8 as well as improved optical performance and a few other improvements. I am very excited to see how this lens performs. I am hoping that it is sharper at 300mm f2.8 and that the af is faster than the previous none OS version. This lens with Sigma's APO 1.4x EX DG tele converter might be the only option I have for a long focal length zoom for motorsports photography that I can somewhat afford. Hopefully the MSRP isn't raised above the current $4200 price tag. A 200mm zoom lens just isn't long enough for me, I need +300mm. So far this Sigma lens fits my needs and hopefully my budget. Thoughts on the new OS lens?