Seconded. I
frequently mistype L/R as up/down, and this is
infuriating when striking 'command' + arrow to go to the beginning/end of the line (an
extremely common op for me), and instead going to the top/bottom of the file, completely losing my place.
(Of course that particular problem would be less of an issue if the keyboard had home/end/pgUp/pgDn, which I'm still sore about, years after they got rid of them).
Arrow keys are so important I might almost want them all full size, in a "+" configuration.