I never notice the 90 frame lines when shooting 28 on a digital. What I hate is the incomplete lower frame lines for the 50 on my M9 and Monochrom. it really messes with quick composition. This does not happen with the 50 frame lines on my M6, but the revival M6 is not the same, with an incomplete 50 frame line along the lower edge Like the modern digital.
What is the same in the revival M6, according to the manual, is the extent of the inner frame lines, like 75, 90 and 135. What I notice in the meter-less Leica MA instructions is that the inner frame lines are more subtle for 75 and 135, reducing the clutter for a 35mm and 50mm view, making the MA even more like an M2 through the viewfinder as well as in its external shape and controls.
If I didn’t have an M6, suddenly an almost AUD$10,000 camera here in Melbourne, or an M2 I’d buy an MA, also now almost $10,000. From 1958 to now the current meter-less Leica film camera is virtually the same machine except for the rapid loading, available for an M2 for 60 years If you wanted it.