In saying that you guys need to be carefull what you say. As there are pine architraves used by major builders then are very thin and flimsy and cost only 50% of the price of MDF.
Pine isnt the bees knees its **** timber as well soft and also rots very easy. The chipping people discribe is due to the fact the builders have used water based paints which are weaker.
In this instance I am the builder... So I know exactly what paints have been used
I have used haymes ultra premium oil based enamal 3 coats thinned down on a coat of under coat and I couldnt chip it if i tried. the mdf would just dint. Sounds like you may have issues with the painting stick onto the timber.