This lens is from Canon's consumer range and it's designed to be a good all rounder. It succeeds superbly.
The lens is a nice weight, it feels substantial and well built. A full time manual focus ring is on board as well as a distance scale. The focus and zoom rings are smooth and the whole package feels right.
Now down to the nitty gritty - image quality. The image quality is simply superb but it does need a little consideration to get the best from it and I'll explain how. At the extreme ends of the focal length the lens is soft, more so at the 28mm end. BUT if the lens is stopped down to anything around F10 and above the image sharpness is unbelievable. Now I realise this isn't possible in every situation but images will be more than acceptable at any f-stop but when they are stopped down they are utterly pin sharp.
As you work through the middle range of the focal length say 45 - 90 the lens is very sharp, stopping it down to F8 and above just enhaces this, until going a little soft at the maximum focal length again.
If you're sticking this lens on a DSLR with a cropped sensor remember that you'll get a focal length range of 45mm to 170mm so if you're looking to this lens to give you semi-wide angle at the bottom end it won't really do it. What you do get is a very usable range of focal lengths and an excellent all-day lens for under £200. The lens also focuses all the way down to 50cm - a nice little bonus in my book and it allows some excellent macro shots.
The lens is very, very good value. For under £200 you get superb image quality, good build, full time manual focus, smooth operation and all day, all situation usability.
It takes 58mm filters.