My clothing inside leg is 28"/29", I prefer the latter, but an unusual
size, and 28" fits better than 30", depending on acceptable crumple.
I measured both my bike today, centre of the crank along the tubes
to the top of the saddles, the road bike is 29", the folder 28.5".
Seat height is set so my legs will lock out using my instep over
the pedal. i.e.very near as high as it will go, with no consideration
of being able to touch the ground sat in the saddle for the height.