The quality varies. The most important consideration is that they are comfortable. WITH a heavy pair of wool socks on. Would generally be one of last purchases. Before purchasing, you should check with your unit.
Some units desire to be equipped with the same musket that the original unit carried.
Occasionally, a second hand weapon may be purchased but make sure someone knowledgeable inspects it before purchase. Even though you will not be firing live rounds, a defective weapon is a danger to you and your filemates. Once you have your musket you need a bayonet. They are different for each type. Make sure when you purchase your bayonet that you try it on the musket and that it seats firmly and locks into place.