The above is a test model, that everything happens to have worked well and he's table ready is a bonus, what's important was to test out the main colours for the army, in this case being metal, the tail, fur and test some shortcuts with using washes (it's a Skaven army I'd feel bad if it was something else. Moving on). It's hard to overstate the use of painting a test model with regards to trying out technique or colour scheme, or making sure you like the army you want to paint. For example if I'd painted some Savage Orcs before I started out with the army, I'm not sure I'd have bothered, they're loaded down with too much detail - rocks, feathers, twine, bone, wood, tattoos, furs etc.
As much a painting this one model was an informative experience, there are vast bits of information that painting one model can't supply. At a very basic level there are details on other models not shown on this one that I don't know how I'll be painting, brass detail for instance or warpstone, all painting challenges I'll have to tackle when I get to them. The model also only displays one colour scheme. While on an uniform army, such as Space Marines, this isn't an issue, I'm going to be painting my Skaven as diversely coloured as I can without overspilling into a riot of colour. This means different coloured fur, different coloured clothes, and different combinations of such.
Even if the model was so overloaded with detail to cover all of the above, or I painted enough test models to cover the main colours I intend to use, there is one thing, of particular import that can't be shown without taking the dive and painting a whole unit and that's if a regiment's colour scheme holds up en mass. There's no way to know beforehand, if a unit (or at a bigger scale, an army) is going to work as a whole with a mix of different colour schemes.
Fingers crossed that unlike the Necrons (they will grace these pages once again, soon) I don't have a change of heart mid way through. My only reservation at this point is that I want to move away from GW's studio scheme of black/red/white, but this does seem to be the scheme best suited to the army. Clearly I need to do more test figures....