In a positive turn of events Overkill, the makers of Payday 2, have added safe drills (read chest keys) to the possible pool of rewards after you successfully complete a heist. If you are confused about why this is worth a news report I'd suggest you start with the previous article. The addition of random microtransactions with in game benefits was so poorly received that the majority of the Payday community united against the developers and voiced their complaints, some more pleasantly than others.
And now that the safe drills are available as in game drops one would think that the whole ordeal is over, the people have won. But things aren't always that simple.
As many have pointed out, the drop chance for the drills is unknown, but given that the system is designed to make money I can't imagine its a very high chance. However, that is not the actual problem, the bigger issue Overkill has skirted around is the fact that these skins come with in game benefits. And not only do they come with in game benefits, they are also completely random so you might buy 5 chests and get skins for guns you don't even own while completely missing the weapons you actually use.
To me this whole thing is silly, Overkill seemingly copied the CS:GO chest system and that in itself is fine, CS:GO has a very fair microtransaction model. So why then have they added stat boosts to these skins? It has been proven time and time again by Valve, our hat overlords, that people are willing to dish out frankly insane amounts of money to look cool, you don't need to upset the balance of the game in order to get people to buy cosmetics.
Simply having a chest with some great skins in it would have been enough and the otherwise great Crimefest wouldn't have its reputation tarnished on day one.