A: No, Gersh writes amulets, and there is a significant difference here.
It is better to order a kosher mezuzah from a certified STa”M scribe or buy it at a certified kosher store. In other words, obtain it from a verified, certified and kosher source. The writing and use mezuzas is a daily part of traditional Judaism, part of Halacha, i.e. part of the Jewish Law; therefore, it is better to get them from those whom law and tradition advise, means from certified kosher scribes.
As stated above, the preparation and use of amulets does not apply to the daily practice of Judaism and one will not find a true amulet in the same place where he can find kosher tefillin and mezuzas. Person can be experienced and kosher STa”M scribe, but at the same time, he might not posses an actual knowledge about true amulets. Needless to say, there are very many blessings and traditional inscriptions which are well known to many scribes and which can be defined as amulets. The use of such items has a more traditional than practical meaning. However, the properly prepared amulets, with the permission of the Al-m-ighty, can turn the order of occurrences and the flow of events in our reality to a better, desired direction.