Terrific for many situations

My first and lasting impression was, and is, "wow"! This thing is really a solid, well built piece of equipment. I am an amateur at best and am not familiar with all the specs of lenses etc. I purchased it to have at least one decent lens that I could use most of the time and not have to deal with a bag full of equipment. I got what I wanted!
I use it 95% of the time. The other 5% is taken with an EF-S 10-22. I have a 20D, which looks and feels like a toy when this glorious monster is attached. Did I say monster? At close to four lbs, it may qualify. Once I got used to lugging it, I appreciated the fast focus, terrific image stabilization and picture quality that I expected from this "not cheap" item. I love this lens and it's helping to strengthen my back.