I recall situations where persons denied actually getting their gun after passing all BG checks ending with dire and even fatal consequences, particularly women victims of domestic violence seeking a means of self defense.Washington Gun Law President, William Kirk, discusses a ruling out of the United States District Court for the State of Maine, which has found that the state's mandatory 72 waiting period is without historical support and is therefore unconstitutional. While the ruling is likely to be appealed such that this case is a long way from over, it does provide some excellent insight about arguments that can be used in other states in challenging these laws.
https://youtu.be/J1lJq9drxpM?t=91