I would go for a recognized brand. The lower end brand brushes, although more expensive, are way better than any cheap ones you will get, and you will be able to get spares for them much easier. Cheap ones tend to be poorly manufactured, which makes them much harder to use, and parts for them are not durable. You will most likely spend more money trying to get one to work properly, and then end up buying another one anyway. You could get lucky, an get a good one, but even so parts won't last, so you are better off spending little more to begin with. I would choose a brand that is easy for you to be able to get parts for. As you are going to be painting models, a gravity fed or side fed brush might be better than a siphon fed. Not sure what scale your models are, but a bottle underneath the gun might get in the way? Just a thought. Also will you want to use waterbased paint or urethane? Solvents damage seals, so if you do want to use them, you will want a gun that has Teflon seals. Iwatas do, not sure about oter brands.
... I used to paint ceramic stuff years ago and thought about using my AB to do a couple now. Not until I get better on paper that for sure. 
