Its funny...manufactures rely on a few things, the quality of components, the quality of assembly, their customer service and their reputation.
A good friend of mine owns a shop and tells me he has more returns on DD stuff then any other right now and that it changes...tomorrow it could be brand X.
What I have learned is that companies go through cycles, sometimes their very good and sometimes their not. A perfect example is Colt years ago almost went out of business and the quality of their goods was shit*.
So to answer the OP's question, Core is producing very good products right now and DD I cant say the same. Its a very competitive industry and those that have their shi* together are producing very nice equipment at great prices right now.
In short, if I had a choice, I would go with the Core, you cant beat the quality for the price point. Others will tell you that the stamp is more important than everything. I will tell you that I don't care about the stamp...I care that its there when I need it.