I understand that micro needling devices have different settings representing depth (ranging from .25-upwards of 3). Sometimes patients are asked to help select the settings. Can you give any guidance on making an informed choice? For example Is it possible to get any results at all from low settings (say, under 1.0) with micro needling and PRP? Conversely, is there a risk of injury at higher settings and if so what is the danger zone? What range is typical. Thanks!