I am getting 11-16 replaced but realized I don't have a good wide angle lense for indoor shots when I cannot back up enough. I primarily have 35/1.8 on my camera, have 28-70 that let's me get a little wider, but won't carry both at same time. There are alot of sites comparing the UWA lenses. I specifically like it's wide aperture for video and have read it may be sharper, so didn't want to get a different UWA lense. The 18-55 (<$100 refurbished, cheaper on craigs list) is light, not bad AF, and 3.5-4 aperture in the 18-20mm range. Curious how it compares to the UWA zooms in this range if both lenses are @4,@5.6,@8. Any practical experience with these two lenses?