I have both Armalite A lowers and DB10 lowers. I'm a little confused on the nature of the question, but I'll check what I can to help you.
Are you worried about magazine fitment between the two, or upper compatibility? I just finished a build using an A lower with a B upper, and I had to machine out the mag stops in the upper and also machine a pocket for the bolt catch paddle in the upper, but the upper fits both lowers fairly well.
Are you wanting pics of DB uppers in Armalite lowers and vice versa, or something else?
I will say that magazines are bitch either way. Some fit, some don't. Take your lower with you to the gun show lol