This is a new lens to enter the fold. I was actually looking at the 25 f4 but I got such a good deal on this one I couldn't say no. One thing really does bother me when using these rangefinder lenses on the Nex system is the colour shift at the edges of the images. This is not only restricted to the Nex-7 as you will see in the following images. I used this lens on the Nex-5N and it is still visible.