I have moved to mirror less camera recently with XT1 (4 months ago). I have 18-55 kit lens, 23 1.4r and ordered a zoom to go with it. I still own a Nikon DSLR with 18-300 lens. Comparing this to any other lens in it's class, you can clearly see why this is a winner. The zoom function is smooth, aperture ring on the lens is added bonus (just note that there are no marking on the lens and you have to see it in electronic viewfinder (I never read manuals so missed this part). Autofocus might not be extremely hard but it sure works. I would recommend this lens highly (atleast until Fuji comes with weather resistant ultra zoom lens).