So far, I've been using the Sony A7R4, the Sony 90mm in conjunction with the SMC 1, and the Weefine WFL06S. I'm extremely satisfied with my setup and am continually impressed by the quality of my super macro images with the Weefine. I think, however, that the MFO-1 offers a great opportunity to improve on the capabilities of the 90mm (autofocus, focus breathing). One thing that's missing for Sony underwater photographers, however, is the ability to dive in black water. From what I've read, the MFO-3 should eliminate this disadvantage. There are rumors about a new 100mm GM macro lens—but I also think that all four lenses will still work with the new one and are therefore a good investment for the future. I think it's time to go shopping again... What I'd also be interested in is whether the SMC 3 offers any added value over the Weefine - perhaps someone here has some information on that. Best, Wolf