Not a bad little lens for $350 on ebay. I gave it a little help cranking up the detail, v detail and reduced coring. Of course weakest @ 400mm but holding up nicely until around 350mm. Good lens to have in your kit when you need that extra reach. But at f-4.5/5.6 I'd only use it outdoors. But I shot this early morning so there wasn't a ton of light.
http://vimeo.com/25827139
http://vimeo.com/25827139