The price for the back goes up about $20 in a few days, and I am very tempted by this… is I stay square something that will be able to take advantage of the RB67?
Instax colors are great, but the exposure can be tricky (the EI varies by a couple stops between bright and dull light, and reciprocity is terrible). At least it's inexpensive; if you buy more than a single pack at a time, it's about the same cost per frame and 120 color negative film plus processing (even a little less if you can't do your own C-41).
I just pulled the trigger, although I am realizing now that a. Instax square is expensive, and b. since I don’t have a WLF I will constantly have to take the prism off to eject the pictures… it might be going up for sale at pre-order price person if I don’t like it.