I will probably get killed by many guys here but if you are scared about hairloss, I would run the primo alone at 400/w with no test . I've done that several times with no problems for the same reason, primo is IMO one the few AAS that you can run without test and no problems, I know people that use it as a bridge between cycles (which is not a good idea really but you see the point)
Also you will see how primo affects your hair by itself