'Splain to me Lucy.. Mamiya Floating Element Lens

[flavio81]

Note the 140mm would be better than the 127mm, but I don't have the handbook for it... The 140 is a double Gauss (7 element - the rear inner group floats) the 127mm a triplet (5 elements), I'd say the 90mm is already a inverted telephoto.

You are correct. The 127mm is a 5/3 design, of identical design than the 80/2.8 on the Mamiya TLRs. The early 90/3.8 looked like a double gauss with a wideangle converter on top (!) and the 90/3.8C is an inverted telephoto.