Pictured below are the brand of water-based acrylic paints that I've been using since my Gundam building days many many moons ago. The Japanese company that makes them is called Gunze Sangyo & I like using them for several reasons:
1) They have a very wide range of colours, especially interesting metallics.
2) They provide decent coverage on the model.
3) They are cheaper than GW paints.
4) They are hell easy to strip; you won't believe this: soak the painted model in soap & water & voila! No brushing even.
The only GW paint I use currently is Chainmail & that's only because Gunze Sangyo shipped in several batches of defective Silver paint at the local hobby store. Hmpf.
The main red & black colours of the armour are actually "Russet" & "Metallic Black":
"Wood Brown" (for pouches, holsters & leather stuff) & "Burnt Iron" (alternate weapon colour):