The almost perfect lense

This is an incredible piece of lense and I am extremely satisfied with the purchase. Its got almost everything I wanted, IS, large aperture for a zoom, ultra fast focusing with USM, superior image quality in a wide angle lense. The first day I bought it, I used it in an cocktail party with extremely low light. The images came out beyond my expectations using only ISO 200 with a fast aperture and IS.

There are only 2 major complaints that I have with this: 1) I wished that it was a 17-85, but that would tremendously boost up the size and price of the lense with the same specs 2) It costed too much ($500 more) compared to the closest competitor of the Tamron 17-50 2.8. For the extra 500, we get only IS, slightly better images, extra 5mm, better and faster focusing, a more expensive USM, full-time manual focus, and better compatibility with canon body (there has been some compatibility issues with non canon lense when standards and bodys are upgraded)

Some points that I would like to give my opinions on what I have heard:
1) This is not an L Series lense: The image quality is as good and in some cases better than the L lense. Many sites can confirm this. I think canon did not give it the L name is because it is for ef-s mount (currently there are not L lenses that are ef-s mount), and it is not weatherproofed in metal (also no hood and other accessories, but that can be changed anytime)
2) will not last a long time because it is not weather sealed and wrapped in metal: true, but if you take good care of it, it will last just as long