People say it's built the same, but the 11-16mm/2.8 feels much more plasticy! The zoom ring makes a "scraping" noise, sort of like plastic against plastic. The focusing ring also sounds plasticy. The whole lens just feels more plasticy. The hood is harder to fit on as well. The change from AF to MF also is more "slippery" then the 12-24mm/4, and feels like plastic. Am I just missing my 12-24mm/4, or have other people experienced the same?