I have used TBII & III, Unibond 800, with great success, but finally got around to smooth on. I think I like it best. I have started using a thickness planer for backings and tapers and the surface is pretty slick when it comes out of the planer. I have made a couple of glue ups with the smooth on straight off the planer with no additional prep or rough up, and so far no problems. I have roughed up the surface with 36-80 grit sandpaper in the past, though.