I've also been painting some bloodletters and thought I'd give the new washes a go.
My typical formula is to spray prime Blood Angel Red followed by a basecoat of black. I'll do the brass next.
Normally, I'd wash Blood Angel Red with a mix of Liquitex Paynes Grey/Vallejo Glaze Medium/Dihydrogen Monoxide (left). I also tried the Badab Black (right) and got almost the same result ... though it sure is nice using it straight out of the pot.
My primary concern here would be quantity. Liquitex is relatively cheap and I can blend any consistancy I want. However, for small jobs, like the Hammerhead I'm working on, the Citadel wash was a very nice product, especially for lining.
Next, I'll try out Devlan Mud vs. Liquetex Burnt Umber on the brass pieces.