Anyone have experience of doing this?

Aqua regia or aqua regis (Latin for royal water or king's water) is a highly corrosive, fuming yellow or red solution, also called nitro-hydrochloric acid. The mixture is formed by freshly mixing concentrated nitric acid and concentrated hydrochloric acid, usually in a volumetric ratio of 1:3 respectively. It was named so because it can dissolve the so-called "royal metals," or noble metals, gold and platinum.
I can get hold of the acids, but I've been reading that the 1:3 ratio isn't as straightforward as it seems, as we're talking moles rather than volume (contrary to what the wiki entry quoted above says). Given that my chemistry knowledge is distinctly lacking, I'm hoping someone can offer useful advice as to the production of aqua regia.

(to the curious, basically I'm thinking of doing this because I can buy 20ml of pre-mixed aqua regia for about £25, and I can buy 2.5 liters of hydrochloric acid and 2.5 liters of nitric acid for about £50, and paying 250 times the cost of the constituent parts just peeves me :boom)