I selected the radeon 9200 as my primary and the Rx 2x0 as the secondary.
Right now it's accurate as my XE is running 24/7 with the 9200, while my X1000 is mostly off, as I'm still working on getting it ready to take the place of my XE, but eventually the Rx 2x0 will be my main card.
I didn't count the 5450 or whatever is in the X5000 as it's not being used at all.
Did your XE have the DMA fix applied. If not can you test if an Rx 2x0 card will work in the XE at some point? You'll need a PEX8112 based PCI to PCIe and if the Rx 2x0 card isn't a low profile variant you'll also need PCIe x16 flexi extender so you can place the card outside the case for testing.