if been thinking on selling my 50L and put some extra money to buy the 24-70... I dont want to get rid od my 24L ii, i like it too much. but if the 24-70 is as good as they say i might sell the 24 as well. The 24mm is only usable after 2.0 before then is has a lot of vignetting specially for astro photography and a little soft in low aperture. after F2 is amazing