I would guess, they are going to shoot equally about the same. Both are going to be great shooters. The difference will come in the cleaning of the rifles. The Black Diamond with an open breech, will fowl the scope if you use one. Not that you can not clean a Black Diamond but the Omega would clean much easier.

One advantage of the Black Diamond is there are three different ignition systems for the rifle, it is open breech if that is a required part of a State hunting law, and the stock and barrel is floated. So as long as you rest the rifle on the stock, the barrel is always in the same position. I do not think the Omega is free floated in the barrel.

I have a Black Diamond XR and it is a great rifle. If you don't mind spending an extra five minutes when you clean the rifle, it would be hard to beat this rifle....