I just upgraded to the A7RIII in nauticam from a Lumix LX10 in nauticam. On the LX10 I had the WWL-1. Reading reviews seems like using the WWL-1 with the Sony 28MM will turn out some great pics so thats what I'm deciding to go with. Thanks for the info and hope to get some more tips and will update how my setup works when we can start traveling again!