generally the 65 will be better, it's a less ambitious lens in terms of angle of view. but, it depends on what your criteria are. For the "sharpest" RB lens, it's not going to be either one of those 2 probably. Ideally, keep both - they differ enough in angle of view that it is useful to have both of them. I have the RZ versions and there's not much overlap in terms of functionality.