Unfortunately, this does not change the default COGS account when adding a new Item.  it only changes the name of the "Purchases" account, and it remains the default account.  I can't understand why default COGS account cannot be chosen by the user.  Makes no sense at all.  Many users will bring over historic data from their prior accounting system and will already have their chart of accounts structured.  

Please share if there is a way to change the default COGS account when creating a new "Product" in the Products and Services list.