I recently acquired a Mamiya 7ii and really like it and the 6x7 format. I used to do a fair amount of close up work in 35mm and I am toying with the idea of getting the macro kit to take advantage of the M7 lens quality. Has anyone here got any experience of this? Alternatively a used RB67 might be better. I have a Bronica SQA which doesn't get much use, but want to move up to 6x7 now for this.