This is a good value for money and delivers adequate image quality for the price tag. Some people said that this lens is crap. But compared to what ? To a L series lens ? Donīt be ridiculous, of course they are completely different products !
The second mistake is testing it in digital cameras. Please test it in a film camera, with a Fuji Provia 100F, tripod mounted, before posting ridiculous comments.
This is not a professional lens. Itīs a prosumer product and gives you honest performance. IS works great. The only odd thing is that images taken with IS on arenīt so sharp when the camera is tripod mounted, so turn it off when using it this way.
I recommend using a HOYA HMC Skylight 1B filter. This lens has several large glass surfaces, so please donīt mess the image quality using a cheap filter. Multicoated high quality filters are a must if you want a good quality image.
Color rendition is good. Pictures are very sharp from F8 and up. Of course wide open on the tele end the image will be not very sharp. If you really want this, buy a L series lens ok!
I used this lens in both EOS-300 and EOS-350D.