Another factor to take into account is the control strategy of the unit. Some manufacturers handle it differently.

E.g company A may allow the unit to ramp the compressor up to say 80% speed before the unit is allowed to start ramping back down to control the set point. In that time the larger unit may generate too much cooling and the unit may cycle off before its hand chance to adjust its compressor output to the load requirements.

Company B may allow a gradual ramp up of the compressor gradually from 0-50%, also the larger units running at 50% will not dehumidify as well as the smaller unit running at 100% as the evaporation temperatures and pressures will be different. Yes you will get cooling but it may not remove as much humidity.