I still do not understand that film flatness issue with this camera. I mean, the wider the film guides the more flat the film.
It's the lack of rollers either end and the cut-away for 127 that's the issue, those wide giudes only help in one plane. So when the film's wound on it doesn't necessairly tighten flat across its width.
We needs to be remembered that when you have simple lenses any anomalies in film flatness are less important anyway.