If you want to see a lot of samples from a particular lens, check out pixel-peepers.com.


Here's for the EF 70-200mm f/4 (both IS and non-IS):http://www.pixel-peeper.com/lenses/?lens=14. Looks like you can't separate the IS from non-IS, but the model does show in the metadata so you can manually sort through them.


What are you planning on shooting with it? I always say if you can afford it, get the IS version. I own the IS version and it's my most used lens after my midrange zoom. Speaking of midrange zoom, you could maybe use an upgrade there first. The two zooms you have are less than stellar. On your 450D, I think you'd love the Canon EF-S 15-85mm f/3.5-5.6 IS USM. Unless you do a lot of photos above 85mm, I'm thinking you'd benefit more from this type of lens.