I would recommend the power cords.Far too many power plant/conditioners affect the power drawn by the component.Any time you insert a device into the electrical delivery system,you will deal with capacitance and inductance.This will effect the ability of a system to draw necessary current/voltage from the wall outlet.Unless your local electric company is absolutely terrible,you will probably be "throwing the baby out with the bath water".Many cords and conditioner/plants are available with retun policies.Don't leave home auditioning without one.
This is only my opinion and you know what that is worth.
This is only my opinion and you know what that is worth.