What's the best product for filling in the flaws in the woodwork prior to finishing? At the moment I'm using Miniwax wood filler but I'm not convinced it the best thing as it lack the ability to fill in small imperfections. I'm not looking at finishing my project with stain or varnish so the color of the fill isn't important. It just needs to fill the smallest of scratches in the woodwork and not show through in the future. Any suggestions...?