The choices should be between the Matrix and Asus's offering of the 280X. In line with that, I'd go with Asus 280X simply because it'd be almost the same BUT you have additional features waiting for those will choose these newer cards, even if "rebadge" is written (partly) all over it.
By the way there's a vid on YouTube showing how quiet Asus's 280X is compared to the MSI, and it is a tiny bit better than reference, too.