Hi Shadowman,
I would almost certainly use handheld, unless it proved really unweildy.
Unless I change to a D90 or better body, I'm stuck with manual focus on this lens as it has no internal SWM motor. I'm just not sure my eyes are up to manual focusing, I can do it on tripod at f2.8 with plenty of light, but in the field, at f5.6 ....
Like the VR
Like the focal length range
I find in practice I up the ISO to get shutter speed well above 1/1000s anyway for birds in flight, so I guess that makes VR less useful for camera shake on the image itself, but I bet it helps focusing too - I like to watch it kick in at 200mm (in V/F), so at 400, it'll be twice as useful when handheld.
Thanks,