IPFs aren't unique or a 'perfect' way of preservation.
Magnetic flux varies from disk to disk and so an IPF (created from the RAW 'magnetic' read data) is unique to that one disk. It is therefore possible to have a different image for every disk of the same game out there.
Look at the recent addition of 'Unofficial IPF' added - dumped and created by a member here. Same games, but different images.
While Kyroflux is probably the most accurate method we currently have for preserving magnetic media, it's a long way off being a preservation project compared with groups dealing with ROM dumps and Optical media.
While I've always had an avid interest in SPS because of Amiga and Spectrum, it's the only reason I dat them for No-Intro.