If I may add my recent experience to this, I've recently started using good quality acrylics more and more--Vallejo and Andrea.  And I've learned through airbrushing Tamiya acrylics, that they really need to be thinned for use.  I found that that goes for hand-brushing, as well as airbrushing.  I've found that the acrylics go on very cleanly, very thin but covering well.  They don't clog finely engraved details, and they dry to a nice smooth surface, that looks almost like it had been airbrushed.  Even for painting toy soldiers, where I used enamels more than acrylics--I used acrylics for specific colors, rather than for any advantage in the medium--I'm experimenting with using all acrylics, and then just sealing with a gloss varnish at the end.  I'm happy with my results so far, and it makes me think that I can hand-brush acrylics on a larger subject, like an airplane or a tank.  I also want to try hand-brushing a Maschinen Krieger piece, after seeing so many modelers in Japan who paint their models exclusively by hand and who get such excellent results.

So, it can be done, and it seems that proper thinning is key to getting good results.