So I just found some Kryoflux images of a few quite rare Spanish games and was wondering about MAME's stance on flux dumps.
"Unresolved" flux dumps, where you have the raw result of reading multiple rotations of each track are annoying to handle (kryoflux, spc, edd...).
"Resolved" dumps where someone extracted one rotation starting at a fixed position (such as the index pulse, or any position that ensures inter-track synchronization is correct), computed a nice "mean" flux change position, and found where tricky things like weak, unformatted or damaged zones are present are very nice, we love them (woz, ipf, mfi...)
"Cooked" formats where sectors are extracted lose information (contents and sizes of gaps), but it can be information that doesn't really exist in the first place, on unprotected stuff in particular where the "standard" system formatting is used. We handle a billion of them (there are usually like two or three per system).