As a good
IS/OS/VC/VR system let's you increase shutter-times by a factor of 2^3=8 you need a (non-IS) lens that is 3 stops brighter to make handheld shots of the same probability to be free of shake. That normally is quite an investment
there are 2 major pitfalls from using IS and shooting with longer shutter-times:
1. You get more motion-blur from moving subjects (I have encountered a situation where I really ruined a chance to take beautiful pics of moving children with not watching my shutter-speed)
2. Your IS-lens has potentially 2 stops smaller aperture, resulting in double the depth of field. Some people think of this as an added bonus, others regret losing the power to isolate subjects from their background by small dof.
So you have to decide for yourself, what you're more interested in...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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