I'm a fan of deep, dark red. The way I've accomplished this on my models is to undercoat white and then basecoat with Dark Flesh. Then wash the model with very diluted Delvan mud.
Note: It's very important to dilute your washes as you'll be adding a lot of them thought the painting process and you don't want to cover any of the details.
Next step: Take a 2:1 mix of Dark Flesh and Blood Red and go over everything but the darkest recesses. Then was the model with (diluted) Baal Red. This step is what's going to eventually give you that rich red (you'll be repeating it several times). After the wash is dry, take 1:1 Dark Flesh and Blood Red and do some general highlighting. You still want to cover most of the armor, but don't touch recesses. Wash with diluted Baal Red. Add Blood Red as another highlight. It's up to you how far you want to go after this, but I generally add severely diluted Baal Red after every step. If you do that, you'll keep the deep red tone all the way though the highlights when you start adding oranges and even yellows.
It's complicated, but if you practice at it and utilize some blending and layering, you'll have a very smooth, rich red.
But after all that, I say screw the red lol. I want to know how Moo does his blue!!!