I was lucky and managed to get a second hand Canon 100 to 400........it is simply stunning in terms of image quality .It is a heavy beast though I carry a rucksack with my kit but a day at Marwell zoo left with me an aching neck .Mounted on a 50d.
Some I see criticise the push pull zoom but I like it.and have no evidence of sensor dust which some say it causes being a trombone action zoom.
It's not a fast lens in terms of aperture but in good light it snaps into focus with no hunting .
Only just joined so so no galleries yet but will get some up soon.
Hmm,i agree with Matt.im considering hiring out a 18-200mm lens,as thats the lens im considering buying as my main lens.i know some people will think why?mainly being is i dont want to fanny about swaping lenses to get close up shots when there may be little time to change lens.if that makes any sense?at the moment,the most dificult thing is choosing bettween the 3 brands that make the focal length.canon,sigma or tamron.tamron is looking good because of the cost,but i dont think it has a IS or Os setting like the other 2 do.