You can purchase a 209 screw-in part which will allow you to use the 209 primers. Otherwise, stick with the black diamond (that has worked for you over the years). Many people think they just have to have the newest stuff. I believe when you get a gun that does what it is supposed to do, and you feel comfortable and confident with that gun, you stay with it. Just my .02

My black diamonds came with all three ignition systems, musket, #11 and 209, I see no reason for the 209 when musket caps works for ya. I use the RWS flangeless musket caps and slip a piece of surgical tubing over the cap and part of the nipple to seal out the weather. 209 isn't legal here, but even if it was, I'd still shoot the musket caps, they provide plenty of fire, and like you say, the trigger on the black diamond is great, I have 2 of em!!

I bought a stainless when they first came out and it has served me well. It shoots musket caps, 240 black mag sabots and 2 pellets of pyrodex. I get inch groups at 100 yds and 2 " @ 150 (my personal limit) It always goes bang, rain or snow,hot or cold. I only bought it for the Black Powder deer season here in Mo. So I'm a casual shooter and haven't tried the new stuff. But my neighbor showed me a Tc omega that shot 209 primers (the stock would scare a grizzly bearand the trigger was terrible)
But, do I really need such an update using 209 primers ? The trigger on mine is the best I've ever had, better than on my hunting rifles or handguns.
What would you do, go in debt for a more updated rifle or just use what I have ?