Looking good David. White is always a problem, even with enamels, and especially brush-painting. With acrylics, it's virtually a no-go on small areas. White paint, any white paint, requires 'laying -off' fully, that is, brushing out as far as it will go, before the next stroke. With acrylics, this is virtually impossible, as it dries too quick. They might be ok for airbrush work, but still very much in their infancy for 'normal' brush work in modelling, and about 20% as effective, in terms of versatility, as enamels. The main problem is, they were designed for a 'quick fix', ease of use for quick drying, to help the inexperienced, and were developed from synthetic paints made for artists, as a substitute for oils. All very well circumventing the 'experience route', but not so good at covering evenly.