It is a remarkable gun and a wise way to insure that one has a reliable firearm push come to shove.
Most guns I have seen (in pictures only alas....) with dual ignition systems are matchlock as the back up, which to me just makes the most sense. Making a match for the lock is rather simple, even if you don't have ideal match. (recently was thinking that one could use a punk stick we use to ignite fireworks as a decent 'match')
Obviously only a rich patron could afford such a luxury firearm. But I doubt it was for his lordship himself, more likely an arm for a high ranking loyal minion. A firearm made for a noble would be much more ornate. An arm for the basic soldiers would be more lackluster. The lack of inlays, elaborate scrolling and bold heraldry lead me to this belief that it is such a gun one would be issued, not own. But certainly not an arm given to an enlisted/conscripted man.