How would you rate your keyboards?

[franz.b]

I have not owned many calculators.
Casio fx-8000g: it simply worked, neither good nor bad.
HP48s: fantastic at the touch and in the layout. Unfortunately it was fragile and the function key row no longer works.
HP49g: used for a short time, horrible to the touch and not functional arrangement. The enter button had to stay where it was in the previous hp, the "hist" button is double with "up arrow", "+ - * /" positioned above the numeric keys, space wasted around the arrows ...
HP50g: touch similar to 48 and very good but the same considerations of 49 layout.