To be honest, while mirrors can have a beneficial effect, I have not found them to be consistently beneficial. I have a colleague that worked a lot with mirrors related to CRPS, and he found that if the patient was not ready for that level of dissonant experience, the mirror could increase symptoms. In my practice, I have found better success engaging with the phantom limb with similar techniques to PRT vs the visual limb with mirror therapy. It has been easier for me to integrate that practice into their mobility (you cannot carry a mirror everywhere). One difficult aspect is that of healing time (which can be prolonged depending on the reason for the amputation and related to the adherence to wear schedules of their prosthesis if they have it yet) and the formation of neuromas at the residual limb/stump. It can create some difficulty in recognizing the differences between functional and structural symptoms. Chronic phantom limb pain (6-12 months out from the amputation) may be easier to identify as functional with less likelihood of other stuff getting in the way of addressing neural circuit issues.