IMO, the best dangerous game double would be a self cocking hammer rifle.
Operates exactly as a hammerless action BUT you also have the ability to bring the loaded rifle to half cock (safe blocking the actual hammer rather than the trigger) and be able to return silently to full cock.
Also, a quick glace at the rifle tells you it is cocked or if an actual misfire had occurred which is unlikely these days I guess.
The argument against hammer guns is largely overblown today as I doubt anybody is really going after DG without a PH anymore. More of an historical discussion considering many hunters went it alone as far as the shooting was concerned.
Reloading on a standard hammer rifle is a bit slower than a hammerless too I suppose.

One thing is certain, hammer guns are more beautiful than the hammerless!