There are some flawed premises in your argument. 1) The existence of background checks regulates the only market in weapons. It clearly does not as current criminals either purchase off the street or have "Straw Buyers" who can pass the background check buy them for them. There is no real or imagined benefit in increasing Background Checks. 2) The dilution of 2d amendment rights as a result of "common sense" reform has already begun to cost people their rights in NY. Under the SAFE act, police are accessing health records, revoking the firearms licenses and confiscating firearms of people who have never run afoul of the law. This is the inherent evil of the compromise. It opens a vector to criminalize or disarm people without probable cause or due process. A medical professional can and should notify law enforcement when they believe a person is dangerous, and an investigation should be carried out to determine, before a court, whether this is the case. It needs to happen prior to depriving someone of their constitutional rights. There are similar arguments created about the concept of a "transfer" under this legislation. It criminalizes an individual storing legally owned firearms with a friend while away (possibly deployed, or even on vacation) without a background check. This creates felons of a lot of unsuspecting people, who have truly done no wrong.