The 1979 Piper Aztec F that I flew for a while had charts for both square settings such as climb 25"/2500 RPM, cruise at 23"/2300RPPM(which we used), and also charts for over square settings such as cruise of 26"/2400 RPM.
Old timer who flew PA-24's and PA-30's in the 60's, said they always operated them over-square, and always got better than TBO on the engines.
Regarding the max RPM for landing, most of the turbo-props I have flown:
EMB110 props stayed at 91% for Landing,
Beech 90 props at 1700 or 1900 RPM for landing(variation due to various models and if Raisebeck modified etc). Also some of these versions had a requirement in the AFM for the props to be increased to 1900 RPM during an ILS approach.
Beech 200/300 props go up to 1900 RPM for landing for three bladed versions.
Shorts 330, props were placed into climb setting in the event of a go around.