Every case that has come before the supreme court in the last 5+ years has sided with the 2A and not the government. It has ruled in those 5 years that the 2A specifically applies to citizens, that governments both state and local can no longer ban a firearm that is "in common use", and several other issues. Unless the court changes the pattern has been to overturn the entire law with a given limit on how long they have to completely rewrite the law or have it removed completely.
If you read the actual wording of the law it not only bans the purchase, importation, or manufacture of some items it specifically prohibits the posession of several items such as pre 1994 magazines that hold more than 10 rounds. Off that right there the law or at least part of it will be struck down as because it makes it never identifies what you are supposed to do with your already legally purchased magazines which are now illegal. In another part of the bill it says the state police will contact all permit holders for handguns to "ensure" that they don't have pre 1994 magazines which hold more than 10 rounds in their posession, that sounds a lot like confiscation. You can have post AWB magazines that hold 10 rounds but you can only load them to 7 rounds but the pre 1994 stuff is what will ultimately kill the bill.
I'm not sure on the mental health aspect but by federal law when you get a background check (NICS) to buy a firearm in the US that information is supposed to be destroyed within 24 hours on the FBI end. If the mental health check holds that on file that is a violation of federal law. When John Ashcroft took over as AG he ordered all the NICS information destroyed as per law which had not been done in the previous administration. So either they have to find a wonky way around it, or change federal law, or ignore it and wait for it to work thru the court system.
Another aspect many people dont' think about if they don't follow the industry. Look at what Ronnie Barret did. He's owner of Barrett firearms, makers of .50 rifles. When the state of CA passed a law banning private citizens from owning or buying them Ronnie Barrett told the state to fuck off and banned the sale to government agencies in the state. The CHP Swat team had a contract for a bunch of his rifles and he nullified the contract and told them they could buy them on the black market if they wanted at an increased price. Already this morning several law firearms manufactures have come out with the same law as it pertains to NY. Make them available to citizens or purchase them off the 2nd hand market, not from us.
I suppose Remington which is the largest firearm maker in the US will now have to move as they are located in the state of New York and a good portion of their catalog is now illegal to posses or ship in the state of NY. Both Remington and kimber both released statements today saying they were looking at a way to quickly relocate to save the business.