I have never been a great fan of paint brushes with synthetic bristles, before, but I came across these in a local hardware shop a few weeks ago and thought I would give them a go. They are supposedly good for detailed work but I am not quite sure where the "artisan" bit comes in. They are markedly thinner than most brushes and I thought I would try them for a bit of varnishing. I must say, they worked really well for me - they seem to load up nicely without drips, keep their bristles, brush out to a smooth finish and clean up well. At the price they can be considered almost disposable but the used one in the pic must have been used and cleaned at least 6 times now and there is not any sign of the usual stiffening of the bristles (I suspect being thinner helps with the cleaning). I haven't tried them with pigmented paints, yet, but they certainly work well for me with varnish. Worth a try, I think.
Haven't been to the forum for a while so only just noticed this. I have not used this particular brush but have been using cheap disposable brushes bought from Easycomposites and sold for spreading epoxy resin. They have similar looking bristles and turned out to be surprisingly good with varnish.