You can not break a Ballard hammer by opening the action in half cock!!! A Ballard hammer automatically goes into half cock upon opening the lever! But on a Ballard half cock is NOT the same position as most other makers. It is just far enough back to keep the hammer off the firing pin, and most people don't even realize it is in half cock automatically. So there's no way to put a Ballard in half cock and break a hammer. Just totally false.
Ballard rifles were one of the most popular competitive rifles of the late 1800's and early 1900's, and even when Marlin stopped producing them in 1890 they were selling extremely well. Marlin did not stop making the Ballard because of Winchester entering the market in 1885. They stopped because John Marlin was a 5% owner of the Ballard patent, and the majority of profits went to others holding the 95%. And his lever action repeating rifles were selling faster than he could build them; which gave him 100% of the profits. Simple math told him to drop the Ballard, and not a fear of competition from Winchester. There are documented letters written to gun magazines back then lamenting Marlin's choice to drop the manufacture of the Ballard rifle. And it's use and customization for many decades after it ended are good examples of how well loved it has been by shooters.
As for Hepburns, I still would choose mine over the High Wall, or my much loved Rolling Blocks. Just my preference, and opinion on the original question asked.