They look great, Rick. IMO, there is little need for f2.8 on these ultra wides, so an f4-f5.6 is more than adequate for just about all UWA work. I have just been looking up these lenses on the net and the Sigma 12-24 seems to have a loyal following and there is quite a lot of support for it and judging by the images I have seen, I can see why.