There's a reason for the CVA not coming BH 209 ready. The majority shoot pellets. That's what the stock breech plug is set up for. CVA is catering to the majority. At least they offer a breech plug that works with BH 209 now. That wasn't always the case. I can shoot BH 209 out of a bone stock CVA, but everything needs to be perfect. The BH 209 BP makes it easier. We were shooting BH long before anybody made a special BP for it.
When I say T7 freezes BP's. I'm talking compared to BH 209. I run the BP bone dry when using BH 209 and it never sticks. I find that much easier than messing with grease and tape.
As for accuracy? I'm going by those who do a lot of bench shooting. (not me) It seems universal that BH 209 is the winner. I've also read multiple times that T7 and BH are pretty close in fps until you get to heavier conicals and then BH pulls away.
As I said though. I just shoot sidelocks now and Swiss. That doesn't mean I can't still offer help for those who are new to inlines. You made it sound like using BH 209 is a big deal. It really isn't. BH is basically a detuned smokeless powder. It needs some special attention to fire reliably. Some guns fire it bone stock. CVA isn't one of them unless you want to get picky about all the details to make it fire bone stock.